560
+ − 1 // **************************************************************
+ − 2 // p2_deco.c REFACTORED VERSION V2.95
+ − 3 // !! SPECIAL TESTING VERSION - DO NOT USE FOR REAL DIVES !!
+ − 4 // Created on: 12.05.2009 ===========================================================
+ − 5 // Author: chsw -> This version shows the alternative (bailout) stops <-
+ − 6 // -> instead of the stop from the normal dive plan. <-
+ − 7 // **************************************************************
+ − 8
+ − 9 //////////////////////////////////////////////////////////////////////////////
+ − 10 // OSTC - diving computer code
+ − 11 // Copyright (C) 2011 HeinrichsWeikamp GbR
+ − 12 //
+ − 13 // This program is free software: you can redistribute it and/or modify
+ − 14 // it under the terms of the GNU General Public License as published by
+ − 15 // the Free Software Foundation, either version 3 of the License, or
+ − 16 // (at your option) any later version.
+ − 17 //
+ − 18 // This program is distributed in the hope that it will be useful,
+ − 19 // but WITHOUT ANY WARRANTY; without even the implied warranty of
+ − 20 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ − 21 // GNU General Public License for more details.
+ − 22 //
+ − 23 // You should have received a copy of the GNU General Public License
+ − 24 // along with this program. If not, see <http://www.gnu.org/licenses/>.
+ − 25 //
+ − 26 //////////////////////////////////////////////////////////////////////////////
+ − 27
+ − 28 // *****************************
+ − 29 // ** I N T R O D U C T I O N **
+ − 30 // *****************************
+ − 31 //
+ − 32 // OSTC
+ − 33 //
+ − 34 // code:
+ − 35 // p2_deco.c
+ − 36 // part2 of the OSTC code
+ − 37 //
+ − 38 // summary:
+ − 39 // decompression routines
+ − 40 // for the OSTC experimental project
+ − 41 // written by Christian Weikamp
+ − 42 // contributions by Ralph Lembcke
+ − 43 //
+ − 44 //
+ − 45 // history:
+ − 46 // 01/03/08 v100: first release candidate
+ − 47 // 03/13/08 v101: start of programming ppO2 code
+ − 48 // 03/13/25 v101a: backup of interim version with ppO2 calculation
+ − 49 // 03/13/25 v101: open circuit gas change during deco
+ − 50 // 03/13/25 v101: CNS_fraction calculation
+ − 51 // 03/13/26 v101: optimization of tissue calc routines
+ − 52 // 07/xx/08 v102a: debug of bottom time routine
+ − 53 // 09/xx/08 v102d: Gradient Factor Model implementation
+ − 54 // 10/10/08 v104: renamed to build v103 for v118 stable
+ − 55 // 10/14/08 v104: integration of char_I_depth_last_deco for Gradient Model
+ − 56 // 03/31/09 v107: integration of FONT Incon24
+ − 57 // 05/23/10 v109: 5 gas changes & 1 min timer
+ − 58 // 07/13/10 v110: cns vault added
+ − 59 // 12/25/10 v110: split in three files (deco.c, main.c, definitions.h)
+ − 60 // 2011/01/20: [jDG] Create a common file included in ASM and C code.
+ − 61 // 2011/01/24: [jDG] Make ascenttime an short. No more overflow!
+ − 62 // 2011/01/25: [jDG] Fusion deco array for both models.
+ − 63 // 2011/01/25: [jDG] Use CF(54) to reverse deco order.
+ − 64 // 2011/02/11: [jDG] Reworked gradient-factor implementation.
+ − 65 // 2011/02/15: [jDG] Fixed inconsistencies introduced by gas switch delays.
+ − 66 // 2011/03/21: [jDG] Added gas consumption (CF56 & CF57) evaluation for OCR mode.
+ − 67 // 2011/04/15: [jDG] Store low_depth in 32bits (w/o rounding), for a better stability.
+ − 68 // 2011/04/25: [jDG] Added 1mn mode for CNS calculation, to allow it for deco planning.
+ − 69 // 2011/04/27: [jDG] Fixed char_O_gradient_factor calculation when model uses gradient-factor.
+ − 70 // 2011/05/02: [jDG] Added "Future TTS" function (CF58).
+ − 71 // 2011/05/17: [jDG] Various cleanups.
+ − 72 // 2011/08/08: [jDG] Computes CNS during deco planning ascent.
+ − 73 // 2011/11/24: [jDG] Slightly faster and better NDL computation.
+ − 74 // 2011/12/17: [mH] Remove of the useless debug stuff
+ − 75 // 2012/02/24: [jDG] Remove missed stop bug.
+ − 76 // 2012/02/25: [jDG] Looking for a more stable LOW grad factor reference.
+ − 77 // 2012/09/10: [mH] Fill char_O_deco_time_for_log for logbook write
+ − 78 // 2012/10/05: [jDG] Better gas_volumes accuracy (average depth, switch between stop).
+ − 79 // 2013/03/05: [jDG] Should vault low_depth too.
+ − 80 // 2013/03/05: [jDG] Wrobell remark: ascent_to_first_stop works better with finer steps (2sec).
+ − 81 // 2013/05/08: [jDG] A. Salm remark: NOAA tables for CNS are in ATA, not bar.
+ − 82 // 2013/12/21: [jDG] Fix CNS calculation in deco plan w/o marked gas switch
+ − 83 // 2014/06/16: [jDG] Fix Helium diluent. Fix volumes with many travel mix.
+ − 84 // 2014/06/29: [mH] Compute int_O_ceiling
+ − 85 // 2015/06/12: [jDG] Fix NDL prediction while desaturating with the Buhlmann model.
+ − 86 // 2017/08/04: [mH] Switch to absolute GF everywhere and apply safety margin parameters to both models (GF and non-GF), fixes from Ralph Lembcke
+ − 87 // 2017/10/31: [rl] enhancements for pSCR mode and introduction of 2nd deco plan computation
+ − 88 // 2017/12/31: [rl] completion of 2nd deco plan computation and various up-fixes
+ − 89 //
+ − 90 //
+ − 91 // Literature:
+ − 92 // Buhlmann, Albert: Tauchmedizin; 4. Auflage [2002];
+ − 93 // Schr"oder, Kai & Reith, Steffen; 2000; S"attigungsvorg"ange beim Tauchen, das Modell ZH-L16, Funktionsweise von Tauchcomputern; http://www.achim-und-kai.de/kai/tausim/saett_faq
+ − 94 // Morrison, Stuart; 2000; DIY DECOMPRESSION; http://www.lizardland.co.uk/DIYDeco.html
+ − 95 // Balthasar, Steffen; Dekompressionstheorie I: Neo Haldane Modelle; http://www.txfreak.de/dekompressionstheorie_1.pdf
+ − 96 // Baker, Erik C.; Clearing Up The Confusion About "Deep Stops"
+ − 97 // Baker, Erik C.; Understanding M-values; http://www.txfreak.de/understanding_m-values.pdf
+ − 98 //
+ − 99 //
+ − 100
+ − 101 // *********************
+ − 102 // ** I N C L U D E S **
+ − 103 // *********************
+ − 104 #include <math.h>
+ − 105
+ − 106 // ***********************************************
+ − 107 // ** V A R I A B L E S D E F I N I T I O N S **
+ − 108 // ***********************************************
+ − 109
+ − 110 #include "p2_definitions.h"
+ − 111 #define TEST_MAIN
+ − 112 #include "shared_definitions.h"
+ − 113
+ − 114
+ − 115 // ambient pressure at different mountain heights
+ − 116 #define P_ambient_1000m 0.880 // [bar] based on 990 hPa and 20°C at sea level, 15°C at altitude
+ − 117 #define P_ambient_2000m 0.782 // [bar]
+ − 118 #define P_ambient_3000m 0.695 // [bar]
+ − 119
+ − 120 // ambient pressure in aircraft cabin during flying - worst case according to Buhlmann
+ − 121 #define P_ambient_fly 0.600 // [bar], 0.600 bar is the value used by Buhlmann for his flying-after-diving calculations
+ − 122 // 0.735 bar is a typical cabin pressure for nowadays commercial jet aircrafts
+ − 123 // -----
+ − 124 // 0.135 bar safety margin
+ − 125
+ − 126 // constants and factors
+ − 127 #define ppWater 0.0627 // water vapor partial pressure in the lungs
+ − 128 #define METER_TO_BAR 0.09985 // conversion factor
+ − 129 #define BAR_TO_METER 10.0150 // conversion factor (1.0/METER_TO_BAR)
+ − 130 #define SURFACE_DESAT_FACTOR 0.7042 // surface desaturation safety factor
+ − 131 #define HYST 1.0E-06 // threshold for tissue graphics on-gassing / off-gassing visualization
+ − 132
+ − 133 // thresholds
+ − 134 #define GF_warning_threshold 100 // threshold for GF warning
+ − 135 #define GF_prewarning_threshold 70 // threshold for GF attention
+ − 136 #define CNS_warning_threshold 100 // threshold for CNS warning
+ − 137 #define CNS_prewarning_threshold 70 // threshold for CNS attention
+ − 138 #define ppO2_prewarn_threshold 120 // threshold for ppO2 attention (master warnings come through options_table.asm)
+ − 139 #define GAS_NEEDS_ATTENTION_THRESHOLD 0.70 // threshold for gas needs attention
+ − 140
+ − 141 // deco engine states and modes
+ − 142 #define DECO_STATUS_MASK 0x03
+ − 143 #define DECO_STATUS_START 0x00
+ − 144 #define DECO_STATUS_FINISHED 0x00
+ − 145 #define DECO_STATUS_STOPS 0x01
+ − 146 #define DECO_STATUS_ASCENT 0x02
+ − 147 #define DECO_STATUS_INIT 0x03
+ − 148
+ − 149 #define DECO_MODE_MASK 0x0C
+ − 150 #define DECO_MODE_LOOP 0x04
+ − 151 #define DECO_MODE_CCR 0x04 // to be used with == operator in combination with DECO_MODE_MASK only!
+ − 152 #define DECO_MODE_PSCR 0x08
+ − 153
+ − 154 #define DECO_PLAN_ALTERNATE 0x10
+ − 155 #define DECO_CNS_CALCULATE 0x20
+ − 156 #define DECO_VOLUME_CALCULATE 0x40
+ − 157 #define DECO_ASCENT_DELAYED 0x80
+ − 158
+ − 159 // deco engine warnings
+ − 160 #define DECO_WARNING_IBCD 0x01
+ − 161 #define DECO_WARNING_IBCD_lock 0x02
+ − 162 #define DECO_WARNING_MBUBBLES 0x04
+ − 163 #define DECO_WARNING_MBUBBLES_lock 0x08
+ − 164 #define DECO_WARNING_OUTSIDE 0x10
+ − 165 #define DECO_WARNING_OUTSIDE_lock 0x20
+ − 166 #define DECO_WARNING_STOPTABLE_OVERFLOW 0x40
+ − 167 #define DECO_FLAG 0x80
+ − 168
+ − 169 // flags used with integer numbers
+ − 170 #define INT_FLAG_INVALID 0x0400
+ − 171 #define INT_FLAG_ZERO 0x0800
+ − 172 #define INT_FLAG_LOW 0x1000
+ − 173 #define INT_FLAG_HIGH 0x2000
+ − 174 #define INT_FLAG_PREWARNING 0x4000
+ − 175 #define INT_FLAG_WARNING 0x8000
+ − 176
+ − 177
+ − 178
+ − 179 // *************************
+ − 180 // ** P R O T O T Y P E S **
+ − 181 // *************************
+ − 182
+ − 183 static void calc_hauptroutine(void);
+ − 184 static void calc_hauptroutine_data_input(void);
+ − 185 static void calc_hauptroutine_update_tissues(void);
+ − 186 static void calc_hauptroutine_calc_deco(void);
+ − 187 static void calc_tissue(void);
+ − 188 static void calc_limit(void);
+ − 189 static void calc_nullzeit(void);
+ − 190 static void calc_ascenttime(void);
+ − 191 static void calc_dive_interval(void);
+ − 192 static void calc_gradient_factor(void);
+ − 193 static void calc_wo_deco_step_1_min(void);
+ − 194 static void calc_desaturation_time(void);
+ − 195
+ − 196 static void sim_extra_time(void);
+ − 197 static void sim_ascent_to_first_stop(void);
+ − 198 static void sim_limit(PARAMETER float GF_current);
+ − 199
+ − 200 static void update_startvalues(void);
+ − 201 static void gas_switch_set(void);
+ − 202 static void compute_CNS_for_display(void);
+ − 203
+ − 204 static void clear_deco_table(void);
+ − 205 static void clear_tissue(void);
+ − 206
+ − 207 static unsigned char gas_find_better(void);
+ − 208 static unsigned char calc_nextdecodepth(void);
+ − 209 static unsigned char update_deco_table(PARAMETER unsigned char time_increment);
+ − 210
+ − 211
+ − 212 //---- Bank 5 parameters -----------------------------------------------------
+ − 213 #ifndef UNIX
+ − 214 # pragma udata bank5=0x500
+ − 215 #endif
+ − 216
+ − 217 // general deco parameters
+ − 218
+ − 219 static float GF_low; // initialized from deco parameters, constant during all computations
+ − 220 static float GF_high; // initialized from deco parameters, constant during all computations
+ − 221 static float GF_delta; // initialized from deco parameters, constant during all computations
+ − 222 static float locked_GF_step_norm; // GF_delta / low_depth_norm in normal plan
+ − 223 static float locked_GF_step_alt; // GF_delta / low_depth_alt in alternative plan
+ − 224
+ − 225 static float low_depth_norm; // Depth of deepest stop in normal plan
+ − 226 static float low_depth_alt; // Depth of deepest stop in alternative plan
+ − 227
+ − 228 static float float_ascent_speed; // ascent speed from options_table (1.0 .. 10.0 m/min)
+ − 229 static float float_saturation_multiplier; // safety factor for on-gassing rates
+ − 230 static float float_desaturation_multiplier; // safety factor for off-gassing rates
+ − 231 static float float_deco_distance; // additional depth below stop depth for tissue, CNS and gas volume calculation
+ − 232
+ − 233
+ − 234 // real context: what we are doing now.
+ − 235
+ − 236 static float calc_lead_tissue_limit; // minimum tolerated ambient pressure by Buhlmann model
+ − 237 static float CNS_fraction; // current CNS (1.00 = 100%)
+ − 238
+ − 239 static unsigned short deco_tissue_vector; // 32 bit vector to memories all tissues that are in decompression
+ − 240 static unsigned short IBCD_tissue_vector; // 32 bit vector to memories all tissues that experience IBCD
+ − 241
+ − 242 // simulation context: used to predict ascent.
+ − 243
+ − 244 static float sim_lead_tissue_limit; // minimum tolerated ambient pressure by Buhlmann model
+ − 245 static float CNS_sim_norm_fraction; // CNS at end of dive in normal plan
+ − 246 static float CNS_sim_alt_fraction; // CNS at end of dive in alternative plan
+ − 247
+ − 248 static unsigned char temp_depth_limit; // depth of next stop in meters, used in deco calculations
+ − 249 static unsigned char sim_lead_tissue_no; // Leading compartment number
+ − 250 static unsigned char split_N2_He[NUM_COMP]; // used for calculating the desaturation time
+ − 251
+ − 252
+ − 253 // stops table
+ − 254
+ − 255 static unsigned char internal_deco_depth[NUM_STOPS]; // depth of the stop
+ − 256 static unsigned char internal_deco_time[NUM_STOPS]; // duration of the stop
+ − 257 static unsigned char internal_deco_gas[NUM_STOPS]; // gas used at the stop
+ − 258
+ − 259
+ − 260 // transfer variables between calc_desaturation_time() and calc_desaturation_time_helper()
+ − 261
+ − 262 static float desat_factor; // used to cache a pre-computed factor
+ − 263 static float var_ht; // buffer for a half-time factor
+ − 264 static float pres_target; // target pressure for a compartment
+ − 265 static float pres_actual; // current pressure of the compartment
+ − 266 static unsigned short short_time; // time it takes for the compartment to reach the target pressure
+ − 267
+ − 268 // transfer variables between gas_volumes() and gas_volumes_helper()
+ − 269 static float float_depth; // depth of the stop or half-way point
+ − 270 static float float_time; // duration of the stop or ascent phase
+ − 271 static float volume; // computed volume of gas
+ − 272 static unsigned char usage; // gas usage in l/min
+ − 273
+ − 274
+ − 275 // 44 byte free space left in this bank
+ − 276
+ − 277
+ − 278 //---- Bank 6 parameters -----------------------------------------------------
+ − 279 #ifndef UNIX
+ − 280 # pragma udata bank6=0x600
+ − 281 #endif
+ − 282
+ − 283 // indexing and sequencing
+ − 284
+ − 285 static unsigned char ci; // used as index to the Buhlmann tables
+ − 286 static unsigned char twosectimer = 0; // used for timing the tissue updating
+ − 287 static unsigned char tissue_increment; // Selector for real/simulated tissues and time increment
+ − 288
+ − 289
+ − 290 // environmental and gas data
+ − 291
+ − 292 static float pres_respiration; // current depth in absolute pressure
+ − 293 static float pres_surface; // absolute pressure at the surface
+ − 294 static float temp_deco; // simulated current depth in abs.pressure, used for deco calculations
+ − 295
+ − 296 static float O2_ratio; // real breathed gas oxygen ratio
+ − 297 static float N2_ratio; // real breathed gas nitrogen ratio
+ − 298 static float He_ratio; // real breathed gas helium ratio
+ − 299
+ − 300 static float calc_O2_ratio; // simulated breathed gas oxygen ratio
+ − 301 static float calc_N2_ratio; // simulated breathed gas nitrogen ratio
+ − 302 static float calc_He_ratio; // simulated breathed gas helium ratio
+ − 303
+ − 304 static float O2_ppO2; // ppO2 - calculated for pure oxygen at current depth
+ − 305 static float pSCR_ppO2; // ppO2 - calculated for breathed from pSCR loop
+ − 306 static float pure_ppO2; // ppO2 - calculated for breathed in OC mode
+ − 307
+ − 308 static unsigned char char_actual_ppO2; // ppO2 - assumed to be breathed, as integer 100 = 1.00 bar
+ − 309
+ − 310 static float breathed_ppO2; // partial pressure of breathed oxygen
+ − 311 static float ppN2; // partial pressure of breathed nitrogen
+ − 312 static float ppHe; // partial pressure of breathed helium
+ − 313
+ − 314
+ − 315 // Buhlmann model parameters
+ − 316
+ − 317 static float var_N2_a; // Buhlmann a, for current N2 tissue
+ − 318 static float var_N2_b; // Buhlmann b, for current N2 tissue
+ − 319 static float var_He_a; // Buhlmann a, for current He tissue
+ − 320 static float var_He_b; // Buhlmann b, for current He tissue
+ − 321 static float var_N2_e; // exposition, for current N2 tissue
+ − 322 static float var_He_e; // exposition, for current He tissue
+ − 323 static float var_N2_ht; // half-time for current N2 tissue
+ − 324 static float var_He_ht; // half-time for current N2 tissue
+ − 325
+ − 326
+ − 327 // gas switch history
+ − 328
+ − 329 static unsigned char sim_gas_first_used; // Number of first used gas, for bottom segment
+ − 330 static unsigned char sim_gas_last_used; // number of last used gas
+ − 331 static unsigned char sim_gas_last_depth; // change depth of last used gas
+ − 332
+ − 333
+ − 334 // vault to back-up & restore tissue data
+ − 335
+ − 336 static float pres_tissue_N2_vault[NUM_COMP]; // stores the nitrogen tissue pressures
+ − 337 static float pres_tissue_He_vault[NUM_COMP]; // stores the helium tissue pressures
+ − 338 static float low_depth_norm_vault; // stores a parameter of the GF model for normal plan
+ − 339 static float low_depth_alt_vault; // stores a parameter of the GF model for alternative plan
+ − 340 static float cns_vault_float; // stores current CNS (float representation)
+ − 341
+ − 342 static unsigned int cns_vault_int; // stores current CNS (integer representation)
+ − 343 static unsigned char deco_warnings_vault; // stores warnings status
+ − 344
+ − 345
+ − 346 // auxiliary variables for local data buffering
+ − 347
+ − 348 static float N2_equilibrium; // used for N2 tissue graphics scaling
+ − 349 static float temp_tissue; // auxiliary variable to buffer tissue pressures
+ − 350
+ − 351
+ − 352 // 7 byte free space left in this bank
+ − 353
+ − 354
+ − 355 //---- Bank 7 parameters -----------------------------------------------------
+ − 356 #ifndef UNIX
+ − 357 # pragma udata bank7=0x700
+ − 358 #endif
+ − 359
+ − 360 // Keep order and position of the variables in bank 7 as they are backed-up to & restored from EEPROM
+ − 361
+ − 362 float pres_tissue_N2[NUM_COMP]; // 16 floats = 64 bytes
+ − 363 float pres_tissue_He[NUM_COMP]; // 16 floats = 64 bytes
+ − 364 float sim_pres_tissue_N2[NUM_COMP]; // 16 floats = 64 bytes
+ − 365 float sim_pres_tissue_He[NUM_COMP]; // 16 floats = 64 bytes
+ − 366
+ − 367
+ − 368 //---- Bank 8 parameters -----------------------------------------------------
+ − 369 #ifndef UNIX
+ − 370 # pragma udata overlay bank8=0x800
+ − 371
+ − 372 static char md_pi_subst[256]; // Overlay C-code data stack here, too.
+ − 373
+ − 374 # define C_STACK md_pi_subst
+ − 375 #endif
+ − 376
+ − 377 // Back to bank6 for further tmp data
+ − 378 #ifndef UNIX
+ − 379 # pragma udata bank6
+ − 380 #endif
+ − 381
+ − 382 //////////////////////////////////////////////////////////////////////////////
+ − 383 //////////////////////////////////////////////////////////////////////////////
+ − 384 ///////////////////////////// THE LOOKUP TABLES //////////////////////////////
+ − 385 //////////////////////////////////////////////////////////////////////////////
+ − 386 //////////////////////////////////////////////////////////////////////////////
+ − 387 //
+ − 388 // End of PROM code is 17F00, So push tables on PROM top...
+ − 389 //
+ − 390 #ifndef UNIX
+ − 391 # pragma romdata Buhlmann_tables = 0x1DD00 // Needs to be in UPPER bank.
+ − 392 #endif
+ − 393
+ − 394 rom const float Buhlmann_ab[4*16] = {
+ − 395 // Data ZH-L16C, from Bühlmann Tauchmedizin 2002, option 1a (4mn)
+ − 396 // a for N2 b for N2 a of He b for He
+ − 397 1.2599, 0.5050, 1.7424, 0.4245,
+ − 398 1.0000, 0.6514, 1.3830, 0.5747,
+ − 399 0.8618, 0.7222, 1.1919, 0.6527,
+ − 400 0.7562, 0.7825, 1.0458, 0.7223,
+ − 401 0.6200, 0.8126, 0.9220, 0.7582,
+ − 402 0.5043, 0.8434, 0.8205, 0.7957,
+ − 403 0.4410, 0.8693, 0.7305, 0.8279,
+ − 404 0.4000, 0.8910, 0.6502, 0.8553,
+ − 405 0.3750, 0.9092, 0.5950, 0.8757,
+ − 406 0.3500, 0.9222, 0.5545, 0.8903,
+ − 407 0.3295, 0.9319, 0.5333, 0.8997,
+ − 408 0.3065, 0.9403, 0.5189, 0.9073,
+ − 409 0.2835, 0.9477, 0.5181, 0.9122,
+ − 410 0.2610, 0.9544, 0.5176, 0.9171,
+ − 411 0.2480, 0.9602, 0.5172, 0.9217,
+ − 412 0.2327, 0.9653, 0.5119, 0.9267
+ − 413 };
+ − 414
+ − 415 rom const float Buhlmann_ht[2*16] = {
+ − 416 // Compartment half-life, in minute
+ − 417 //--- N2 ---- He ----------------------
+ − 418 4.0, 1.51,
+ − 419 8.0, 3.02,
+ − 420 12.5, 4.72,
+ − 421 18.5, 6.99,
+ − 422 27.0, 10.21,
+ − 423 38.3, 14.48,
+ − 424 54.3, 20.53,
+ − 425 77.0, 29.11,
+ − 426 109.0, 41.20,
+ − 427 146.0, 55.19,
+ − 428 187.0, 70.69,
+ − 429 239.0, 90.34,
+ − 430 305.0, 115.29,
+ − 431 390.0, 147.42,
+ − 432 498.0, 188.24,
+ − 433 635.0, 240.03
+ − 434 };
+ − 435
+ − 436 rom const float e2secs[2*16] = {
+ − 437 // result of 1 - 2^(-1/(2sec*HT))
+ − 438 //---- N2 ------------- He ------------
+ − 439 5.75958E-03, 1.51848E-02,
+ − 440 2.88395E-03, 7.62144E-03,
+ − 441 1.84669E-03, 4.88315E-03,
+ − 442 1.24813E-03, 3.29997E-03,
+ − 443 8.55371E-04, 2.26041E-03,
+ − 444 6.03079E-04, 1.59437E-03,
+ − 445 4.25414E-04, 1.12479E-03,
+ − 446 3.00019E-04, 7.93395E-04,
+ − 447 2.11949E-04, 5.60641E-04,
+ − 448 1.58240E-04, 4.18555E-04,
+ − 449 1.23548E-04, 3.26795E-04,
+ − 450 9.66686E-05, 2.55722E-04,
+ − 451 7.57509E-05, 2.00387E-04,
+ − 452 5.92416E-05, 1.56716E-04,
+ − 453 4.63943E-05, 1.22734E-04,
+ − 454 3.63850E-05, 9.62538E-05
+ − 455 //-------------------------------------
+ − 456 };
+ − 457
+ − 458 rom const float e1min[2*16] = {
+ − 459 // Integration constant for 1 minute,
+ − 460 // Ie. 1- 2^(-1/HT)
+ − 461 //----- N2 --------- e 1min He --------
+ − 462 1.59104E-01, 3.68109E-01,
+ − 463 8.29960E-02, 2.05084E-01,
+ − 464 5.39424E-02, 1.36579E-01,
+ − 465 3.67742E-02, 9.44046E-02,
+ − 466 2.53454E-02, 6.56359E-02,
+ − 467 1.79351E-02, 4.67416E-02,
+ − 468 1.26840E-02, 3.31991E-02,
+ − 469 8.96152E-03, 2.35301E-02,
+ − 470 6.33897E-03, 1.66832E-02,
+ − 471 4.73633E-03, 1.24808E-02,
+ − 472 3.69981E-03, 9.75753E-03,
+ − 473 2.89600E-03, 7.64329E-03,
+ − 474 2.27003E-03, 5.99417E-03,
+ − 475 1.77572E-03, 4.69082E-03,
+ − 476 1.39089E-03, 3.67548E-03,
+ − 477 1.09097E-03, 2.88359E-03
+ − 478 //-------------------------------------
+ − 479 };
+ − 480
+ − 481 rom const float e10min[2*16] = {
+ − 482 // The 10 min Value in float notation:
+ − 483 // result of 1 - 2^(-10/ht)
+ − 484 //---- N2 -------------- He -----------
+ − 485 8.23223E-01, 9.89851E-01,
+ − 486 5.79552E-01, 8.99258E-01,
+ − 487 4.25651E-01, 7.69737E-01,
+ − 488 3.12487E-01, 6.29027E-01,
+ − 489 2.26416E-01, 4.92821E-01,
+ − 490 1.65547E-01, 3.80407E-01,
+ − 491 1.19840E-01, 2.86538E-01,
+ − 492 8.60863E-02, 2.11886E-01,
+ − 493 6.16117E-02, 1.54849E-01,
+ − 494 4.63665E-02, 1.18026E-01,
+ − 495 3.63881E-02, 9.34005E-02,
+ − 496 2.85855E-02, 7.38569E-02,
+ − 497 2.24698E-02, 5.83504E-02,
+ − 498 1.76160E-02, 4.59303E-02,
+ − 499 1.38222E-02, 3.61528E-02,
+ − 500 1.08563E-02, 2.84646E-02
+ − 501 //-------------------------------------
+ − 502 };
+ − 503
+ − 504 //////////////////////////////////////////////////////////////////////////////
+ − 505 //////////////////////////////////////////////////////////////////////////////
+ − 506 ////////////////////////////// THE SUBROUTINES ///////////////////////////////
+ − 507 //////////////////////////////////////////////////////////////////////////////
+ − 508 //////////////////////////////////////////////////////////////////////////////
+ − 509 //
+ − 510 // all new in v.102
+ − 511 // moved from 0x0D000 to 0x0C000 in v.108
+ − 512 #ifndef UNIX
+ − 513 # pragma code p2_deco = 0x0C000
+ − 514 #endif
+ − 515
+ − 516 //////////////////////////////////////////////////////////////////////////////
+ − 517 //////////////////////////////////////////////////////////////////////////////
+ − 518 /////////////////////// U T I L I T I E S /////////////////////////////////
+ − 519 //////////////////////////////////////////////////////////////////////////////
+ − 520 //////////////////////////////////////////////////////////////////////////////
+ − 521
+ − 522 //////////////////////////////////////////////////////////////////////////////
+ − 523 // Bump to blue-screen when an assert is wrong
+ − 524 #ifdef __DEBUG
+ − 525 void assert_failed(PARAMETER short int line)
+ − 526 {
+ − 527 }
+ − 528 #endif
+ − 529
+ − 530 //////////////////////////////////////////////////////////////////////////////
+ − 531 // When calling C code from ASM context, the data stack pointer and
+ − 532 // frames should be reset. Bank8 is used by stack
+ − 533
+ − 534 #ifdef CROSS_COMPILE
+ − 535 # define RESET_C_STACK
+ − 536 #else
+ − 537 # ifdef __DEBUG
+ − 538 # define RESET_C_STACK fillDataStack();
+ − 539 void fillDataStack(void)
+ − 540 {
+ − 541 _asm
+ − 542 LFSR 1,C_STACK
+ − 543 MOVLW 0xCC
+ − 544 loop: MOVWF POSTINC1,0
+ − 545 TSTFSZ FSR1L,0
+ − 546 BRA loop
+ − 547
+ − 548 LFSR 1,C_STACK
+ − 549 LFSR 2,C_STACK
+ − 550 _endasm
+ − 551 }
+ − 552 # else
+ − 553 # define RESET_C_STACK \
+ − 554 _asm \
+ − 555 LFSR 1, C_STACK \
+ − 556 LFSR 2, C_STACK \
+ − 557 _endasm
+ − 558 # endif
+ − 559 #endif
+ − 560
+ − 561 //////////////////////////////////////////////////////////////////////////////
+ − 562 // Fast subroutine to read timer 5.
+ − 563 // Note: result is in 1/32 of milliseconds (30,51757813 us/bit to be precise)
+ − 564 static unsigned short tmr5(void)
+ − 565 {
+ − 566 #ifndef CROSS_COMPILE
+ − 567 _asm
+ − 568 movff 0xf7c,PRODL // TMR5L
+ − 569 movff 0xf7d,PRODH // TMR5H
+ − 570 _endasm // result in PRODH:PRODL.
+ − 571 #else
+ − 572 return 0;
+ − 573 #endif
+ − 574 }
+ − 575
+ − 576 //////////////////////////////////////////////////////////////////////////////
+ − 577 // read Buhlmann tables A and B for compartment ci
+ − 578 //
+ − 579 static void read_Buhlmann_coefficients(void)
+ − 580 {
+ − 581 #ifndef CROSS_COMPILE
+ − 582 // Note: we don't use far rom pointer, because the
+ − 583 // 24 bits is too complex, hence we have to set
+ − 584 // the UPPER page ourself...
+ − 585 // --> Set zero if tables are moved to lower pages !
+ − 586 _asm
+ − 587 movlw 1
+ − 588 movwf TBLPTRU,0
+ − 589 _endasm
+ − 590 #endif
+ − 591
+ − 592 assert( ci < NUM_COMP );
+ − 593
+ − 594 // Use an interleaved array (AoS) to access coefficients with a
+ − 595 // single addressing.
+ − 596 {
+ − 597 overlay rom const float* ptr = &Buhlmann_ab[4*ci];
+ − 598 var_N2_a = *ptr++;
+ − 599 var_N2_b = *ptr++;
+ − 600 var_He_a = *ptr++;
+ − 601 var_He_b = *ptr++;
+ − 602 }
+ − 603 }
+ − 604
+ − 605 //////////////////////////////////////////////////////////////////////////////
+ − 606 // read Buhlmann tables for compartment ci
+ − 607 // If period == 0 : 2sec interval
+ − 608 // 1 : 1 min interval
+ − 609 // 2 : 10 min interval.
+ − 610 static void read_Buhlmann_times(PARAMETER char period)
+ − 611 {
+ − 612 #ifndef CROSS_COMPILE
+ − 613 // Note: we don't use far rom pointer, because the
+ − 614 // 24 bits is to complex, hence we have to set
+ − 615 // the UPPER page ourself...
+ − 616 // --> Set zero if tables are moved to lower pages !
+ − 617 _asm
+ − 618 movlw 1
+ − 619 movwf TBLPTRU,0
+ − 620 _endasm
+ − 621 #endif
+ − 622
+ − 623 assert( ci < NUM_COMP );
+ − 624
+ − 625 // Integration intervals.
+ − 626 switch(period)
+ − 627 {
+ − 628 case 0: //---- 2 sec -----------------------------------------------------
+ − 629 {
+ − 630 overlay rom const float* ptr = &e2secs[2*ci];
+ − 631 var_N2_e = *ptr++;
+ − 632 var_He_e = *ptr++;
+ − 633 }
+ − 634 break;
+ − 635
+ − 636 case 1: //---- 1 min -----------------------------------------------------
+ − 637 {
+ − 638 overlay rom const float* ptr = &e1min[2*ci];
+ − 639 var_N2_e = *ptr++;
+ − 640 var_He_e = *ptr++;
+ − 641 }
+ − 642 break;
+ − 643
+ − 644 case 2: //---- 10 min ----------------------------------------------------
+ − 645 {
+ − 646 overlay rom const float* ptr = &e10min[2*ci];
+ − 647 var_N2_e = *ptr++;
+ − 648 var_He_e = *ptr++;
+ − 649 }
+ − 650 break;
+ − 651
+ − 652 default:
+ − 653 assert(0); // Never go there...
+ − 654 }
+ − 655 }
+ − 656
+ − 657 //////////////////////////////////////////////////////////////////////////////
+ − 658 // read Buhlmann tables for compartment ci
+ − 659 //
+ − 660 static void read_Buhlmann_ht(void)
+ − 661 {
+ − 662
+ − 663 #ifndef CROSS_COMPILE
+ − 664 // Note: we don't use far rom pointer, because the
+ − 665 // 24 bits is to complex, hence we have to set
+ − 666 // the UPPER page ourself...
+ − 667 // --> Set zero if tables are moved to lower pages !
+ − 668 _asm
+ − 669 movlw 1
+ − 670 movwf TBLPTRU,0
+ − 671 _endasm
+ − 672 #endif
+ − 673
+ − 674 assert( ci < NUM_COMP );
+ − 675 {
+ − 676 overlay rom const float* ptr = &Buhlmann_ht[2*ci];
+ − 677 var_N2_ht = *ptr++;
+ − 678 var_He_ht = *ptr++;
+ − 679 }
+ − 680
+ − 681 assert( 4.0 <= var_N2_ht && var_N2_ht <= 635.0 );
+ − 682 assert( 1.5099 <= var_He_ht && var_He_ht <= 240.03 );
+ − 683 }
+ − 684
+ − 685 //////////////////////////////////////////////////////////////////////////////
+ − 686 // calc_nextdecodepth
+ − 687 //
+ − 688 // new in v.102
+ − 689 //
+ − 690 // INPUT, changing during dive:
+ − 691 // temp_deco : current depth in absolute pressure
+ − 692 //
+ − 693 // INPUT, fixed during dive:
+ − 694 // pres_surface
+ − 695 // GF_delta
+ − 696 // GF_high
+ − 697 // GF_low
+ − 698 // char_I_depth_last_deco
+ − 699 //
+ − 700 // MODIFIED
+ − 701 // locked_GF_step_norm/_alt : used for GF model
+ − 702 // low_depth_norm/_alt : used for GF model
+ − 703 //
+ − 704 // OUTPUT
+ − 705 // temp_depth_limit : depth of next stop in meters (if RETURN == true )
+ − 706 // depth we can ascent to without stop (if RETURN == false)
+ − 707 //
+ − 708 // RETURN TRUE if a stop is needed.
+ − 709 //
+ − 710 static unsigned char calc_nextdecodepth(void)
+ − 711 {
+ − 712 overlay unsigned char need_stop;
+ − 713
+ − 714 // compute current depth in meters
+ − 715 overlay float depth = (temp_deco - pres_surface) * BAR_TO_METER;
+ − 716
+ − 717 // compute depth in meters after 1 minute of ascent at float_ascent_speed (5..10 m/min)
+ − 718 overlay float min_depth = (depth > float_ascent_speed) ? (depth - float_ascent_speed) : 0.0;
+ − 719
+ − 720
+ − 721 // allow for 200mbar of weather dependent surface pressure change
+ − 722 assert( depth >= -0.2 );
+ − 723
+ − 724
+ − 725 //---- check if a stop is needed for deco reasons ----------------------------
+ − 726
+ − 727 // switch on deco model
+ − 728 if( char_I_deco_model != 0 )
+ − 729 {
+ − 730 //---- ZH-L16 + GRADIENT FACTOR Model ------------------------------------
+ − 731
+ − 732 overlay float locked_GF_step;
+ − 733 overlay float low_depth;
+ − 734 overlay float pres_gradient;
+ − 735
+ − 736 overlay unsigned char first_stop = 0;
+ − 737
+ − 738
+ − 739 // calculate minimum depth we can ascent to in absolute pressure
+ − 740 sim_limit( GF_low );
+ − 741
+ − 742 // ...and convert the depth into relative pressure
+ − 743 pres_gradient = sim_lead_tissue_limit - pres_surface;
+ − 744
+ − 745 // check if we can surface directly
+ − 746 if( pres_gradient <= 0.0 )
+ − 747 {
+ − 748 min_depth = 0.0; // set minimum depth to 0 meters = surface
+ − 749 goto no_deco_stop; // done.
+ − 750 }
+ − 751
+ − 752 // convert minimum depth we can ascent to from relative pressure to depth in meters
+ − 753 pres_gradient *= BAR_TO_METER;
+ − 754
+ − 755 // recall low_depth dependent on current plan
+ − 756 low_depth = (char_O_deco_status & DECO_PLAN_ALTERNATE) ? low_depth_alt : low_depth_norm;
+ − 757
+ − 758 // Store the deepest point needing a deco stop as the LOW reference for GF.
+ − 759 // NOTE: following stops will be validated using this LOW-HIGH GF scale,
+ − 760 // so if we want to keep coherency, we should not validate this stop
+ − 761 // yet, but apply the search to it, as for all the following stops afterward.
+ − 762 if( pres_gradient > low_depth )
+ − 763 {
+ − 764 // update GF parameters
+ − 765 low_depth = pres_gradient;
+ − 766 locked_GF_step = GF_delta / low_depth;
+ − 767
+ − 768 // store updated GF parameters dependent on current plan
+ − 769 if( char_O_deco_status & DECO_PLAN_ALTERNATE )
+ − 770 {
+ − 771 low_depth_alt = low_depth;
+ − 772 locked_GF_step_alt = locked_GF_step;
+ − 773 }
+ − 774 else
+ − 775 {
+ − 776 low_depth_norm = low_depth;
+ − 777 locked_GF_step_norm = locked_GF_step;
+ − 778 }
+ − 779 }
+ − 780 else
+ − 781 {
+ − 782 // recall locked_GF_step dependent on current plan
+ − 783 locked_GF_step = (char_O_deco_status & DECO_PLAN_ALTERNATE) ? locked_GF_step_alt : locked_GF_step_norm;
+ − 784 }
+ − 785
+ − 786 // invalidate this stop if we can ascent for 1 minute without going above minimum required deco depth
+ − 787 if( pres_gradient < min_depth ) goto no_deco_stop;
+ − 788
+ − 789
+ − 790 // if program execution passes here, we need a deco stop
+ − 791
+ − 792 // Round to multiple of 3 meters
+ − 793 first_stop = 3 * (unsigned char)(0.9995 + pres_gradient * 0.333333);
+ − 794
+ − 795 // check a constraint
+ − 796 assert( first_stop < 128 );
+ − 797
+ − 798 // apply correction for the shallowest stop, use char_I_depth_last_deco (3..6 m) instead
+ − 799 if( first_stop == 3 ) first_stop = char_I_depth_last_deco;
+ − 800
+ − 801 // We have a stop candidate.
+ − 802 // But maybe ascending to the next stop will diminish the constraint,
+ − 803 // because the GF might decrease more than the pressure gradient...
+ − 804 while(first_stop > 0)
+ − 805 {
+ − 806 // Next depth
+ − 807 overlay unsigned char next_stop;
+ − 808
+ − 809 // invalidate this stop if we can ascent one more minute without going above minimum required deco depth
+ − 810 if( first_stop <= (unsigned char)min_depth ) goto no_deco_stop;
+ − 811
+ − 812 // compute depth of next stop
+ − 813 if ( first_stop <= char_I_depth_last_deco ) next_stop = 0;
+ − 814 else if ( first_stop == 6 ) next_stop = char_I_depth_last_deco;
+ − 815 else next_stop = first_stop - 3;
+ − 816
+ − 817 // compute total pressure at the new stop candidate
+ − 818 pres_gradient = next_stop * METER_TO_BAR + pres_surface;
+ − 819
+ − 820 // compute limit for the new stop candidate
+ − 821 if( (low_depth == 0.0) || (next_stop > low_depth) ) sim_limit( GF_low );
+ − 822 else sim_limit( GF_high - next_stop * locked_GF_step );
+ − 823
+ − 824 // check if ascent to the next stop candidate is possible
+ − 825 if( sim_lead_tissue_limit >= pres_gradient ) goto deco_stop_found; // no - ascent to next_stop forbidden
+ − 826
+ − 827 // else, validate that stop and loop...
+ − 828 first_stop = next_stop;
+ − 829 }
+ − 830
+ − 831 no_deco_stop:
+ − 832 need_stop = 0; // set flag for stop needed to 'no'
+ − 833 temp_depth_limit = (unsigned char)min_depth; // report depth we can ascent to without stop
+ − 834 goto done;
+ − 835
+ − 836 deco_stop_found:
+ − 837 need_stop = 1; // set flag for stop needed to 'yes'
+ − 838 temp_depth_limit = (unsigned char)first_stop; // stop depth, in meters
+ − 839
+ − 840 done:
+ − 841 ;
+ − 842 }
+ − 843 else
+ − 844 {
+ − 845 //---- ZH-L16 model -------------------------------------------------
+ − 846
+ − 847 overlay float pres_gradient;
+ − 848
+ − 849
+ − 850 // calculate minimum depth we can ascent to in absolute pressure
+ − 851 sim_limit(1.0);
+ − 852
+ − 853 // ...and convert the depth into relative pressure
+ − 854 pres_gradient = sim_lead_tissue_limit - pres_surface;
+ − 855
+ − 856 // check if we can surface directly
+ − 857 if (pres_gradient >= 0)
+ − 858 {
+ − 859 // no - set flag for stop needed to 'yes'
+ − 860 need_stop = 1;
+ − 861
+ − 862 // convert stop depth in relative pressure to stop index
+ − 863 pres_gradient *= BAR_TO_METER / 3;
+ − 864
+ − 865 // convert stop index to depth in meters, rounded to multiple of 3 meters
+ − 866 temp_depth_limit = 3 * (short) (pres_gradient + 0.99);
+ − 867
+ − 868 // correct last stop to 4m/5m/6m
+ − 869 if( temp_depth_limit == 3 ) temp_depth_limit = char_I_depth_last_deco;
+ − 870 }
+ − 871 else
+ − 872 {
+ − 873 // yes - set flag for stop needed to 'no'
+ − 874 need_stop = 0;
+ − 875
+ − 876 // set depth we can ascent to as 0 = surface
+ − 877 temp_depth_limit = 0;
+ − 878 }
+ − 879 }
+ − 880
+ − 881
+ − 882 // After the first deco stop, gas changes are only done at deco stops now!
+ − 883
+ − 884 // check if a stop is found and there is a better gas to switch to
+ − 885 if( need_stop && gas_find_better() )
+ − 886 {
+ − 887 // set the new calculation ratios for N2, He and O2
+ − 888 gas_switch_set();
+ − 889
+ − 890 // prime the deco stop with the gas change time
+ − 891 update_deco_table(char_I_gas_change_time);
+ − 892 }
+ − 893
+ − 894 return need_stop;
+ − 895 }
+ − 896
+ − 897 //////////////////////////////////////////////////////////////////////////////
+ − 898 // copy_deco_table
+ − 899 //
+ − 900 // Buffer the stops, once computed, so we can continue to display them
+ − 901 // while computing the next set.
+ − 902 //
+ − 903 static void copy_deco_table(void)
+ − 904 {
+ − 905 // Copy depth of the first (deepest) stop, because when reversing
+ − 906 // order, it will be hard to find...
+ − 907 char_O_first_deco_depth = internal_deco_depth[0];
+ − 908 char_O_first_deco_time = internal_deco_time [0];
+ − 909
+ − 910 {
+ − 911 overlay unsigned char x, y;
+ − 912
+ − 913 for(x=0; x<NUM_STOPS; x++)
+ − 914 {
+ − 915 char_O_deco_depth[x] = internal_deco_depth[x];
+ − 916 char_O_deco_time [x] = internal_deco_time [x];
+ − 917 char_O_deco_gas [x] = internal_deco_gas [x];
+ − 918 }
+ − 919
+ − 920 //Now fill the char_O_deco_time_for_log array
+ − 921 //---- First: search the first non-null depth
+ − 922 for(x=(NUM_STOPS-1); x != 0; --x)
+ − 923 if( internal_deco_depth[x] != 0 ) break;
+ − 924
+ − 925 //---- Second: copy to output table (in reverse order)
+ − 926 for(y=0; y<NUM_STOPS; y++, --x)
+ − 927 {
+ − 928 char_O_deco_time_for_log[y] = internal_deco_time [x];
+ − 929
+ − 930 // Stop only once the last transfer is done.
+ − 931 if( x == 0 ) break;
+ − 932 }
+ − 933
+ − 934 //---- Third: fill table end with null
+ − 935 for(y++; y<NUM_STOPS; y++)
+ − 936 {
+ − 937 char_O_deco_time_for_log[y] = 0;
+ − 938 }
+ − 939 }
+ − 940 }
+ − 941
+ − 942 //////////////////////////////////////////////////////////////////////////////
+ − 943 // temp_tissue_safety
+ − 944 //
+ − 945 // outsourced in v.102
+ − 946 //
+ − 947 // Apply safety factors for both ZH-L16 models.
+ − 948 //
+ − 949 static void temp_tissue_safety(void)
+ − 950 {
+ − 951 assert( 0.0 < float_desaturation_multiplier && float_desaturation_multiplier <= 1.0 );
+ − 952 assert( 1.0 <= float_saturation_multiplier && float_saturation_multiplier <= 2.0 );
+ − 953
+ − 954 if( temp_tissue < 0.0 ) temp_tissue *= float_desaturation_multiplier;
+ − 955 else temp_tissue *= float_saturation_multiplier;
+ − 956 }
+ − 957
+ − 958 //////////////////////////////////////////////////////////////////////////////
+ − 959 //////////////////////////////////////////////////////////////////////////////
+ − 960 // ** THE JUMP-IN CODE **
+ − 961 // ** for the asm code **
+ − 962 //////////////////////////////////////////////////////////////////////////////
+ − 963 //////////////////////////////////////////////////////////////////////////////
+ − 964
+ − 965 //////////////////////////////////////////////////////////////////////////////
+ − 966 // Called every second during diving.
+ − 967 // updates tissues every second invocation.
+ − 968 //
+ − 969 // Every few seconds (or slower when TTS > 16):
+ − 970 // - updates deco table (char_O_deco_time/depth) with new values.
+ − 971 // - updates ascent time,
+ − 972 // - sets status to zero (so we can check there is new results).
+ − 973 //
+ − 974 void deco_calc_hauptroutine(void)
+ − 975 {
+ − 976 RESET_C_STACK
+ − 977 calc_hauptroutine();
+ − 978 }
+ − 979
+ − 980 //////////////////////////////////////////////////////////////////////////////
+ − 981 // Reset decompression model:
+ − 982 // + Set all tissues to equilibrium with Air at ambient pressure.
+ − 983 // + Reset last stop to 0m
+ − 984 // + Reset all model output.
+ − 985 void deco_clear_tissue(void)
+ − 986 {
+ − 987 RESET_C_STACK
+ − 988 clear_tissue();
+ − 989 }
+ − 990
+ − 991 //////////////////////////////////////////////////////////////////////////////
+ − 992
+ − 993 void deco_calc_wo_deco_step_1_min(void)
+ − 994 {
+ − 995 RESET_C_STACK
+ − 996 calc_wo_deco_step_1_min();
+ − 997 }
+ − 998
+ − 999 //////////////////////////////////////////////////////////////////////////////
+ − 1000
+ − 1001 void deco_calc_desaturation_time(void)
+ − 1002 {
+ − 1003 RESET_C_STACK
+ − 1004 calc_desaturation_time();
+ − 1005 }
+ − 1006
+ − 1007 //////////////////////////////////////////////////////////////////////////////
+ − 1008
+ − 1009 void deco_calc_dive_interval(void)
+ − 1010 {
+ − 1011 RESET_C_STACK
+ − 1012 calc_dive_interval();
+ − 1013 }
+ − 1014
+ − 1015 //////////////////////////////////////////////////////////////////////////////
+ − 1016 // Find current gas in the list (if any) and get its change depth
+ − 1017 //
+ − 1018 // Input: char_I_current_gas : 1..6
+ − 1019 //
+ − 1020 // Output: sim_gas_last_used : 1..6 or 0 if it is the gas set as FIRST
+ − 1021 // sim_gas_last_depth : change depth in meters or 0 if it is the gas set as FIRST
+ − 1022 //
+ − 1023 static void gas_find_current(void)
+ − 1024 {
+ − 1025 assert( 0 <= char_I_current_gas && char_I_current_gas <= NUM_GAS );
+ − 1026
+ − 1027 if( char_I_current_gas <= NUM_GAS ) // Gas1..Gas5
+ − 1028 {
+ − 1029 sim_gas_last_used = sim_gas_first_used = char_I_current_gas;
+ − 1030
+ − 1031 // If current gas is a deco gas get it's change depth.
+ − 1032 // Set change depth to 0 if the current gas is the first gas or
+ − 1033 // a travel/normal gas, i.e. if it can be breathed at "any" depth.
+ − 1034 if( char_I_deco_gas_change[sim_gas_last_used-1] ) sim_gas_last_depth = char_I_deco_gas_change[sim_gas_last_used-1];
+ − 1035 else sim_gas_last_depth = 0;
+ − 1036 }
+ − 1037 else
+ − 1038 {
+ − 1039 sim_gas_last_used = sim_gas_first_used = 0; // Gas 6 (the manually set one) has number 0 here
+ − 1040 sim_gas_last_depth = 0; // handle it as a travel/normal gas
+ − 1041 }
+ − 1042 }
+ − 1043
+ − 1044
+ − 1045 //////////////////////////////////////////////////////////////////////////////
+ − 1046 // Find the deco gas with the shallowest change depth beyond current depth
+ − 1047 //
+ − 1048 // INPUT temp_depth_limit : current depth in meters
+ − 1049 // char_I_deco_gas_change[] : change depths of the deco gases
+ − 1050 // sim_gas_last_depth : change depth of the currently used gas, 0 if on the gas set as FIRST
+ − 1051 //
+ − 1052 // OUTPUT sim_gas_last_depth : switch depth - only if return value is true
+ − 1053 // sim_gas_last_used : index of the gas (1..5) - only if return value is true
+ − 1054 //
+ − 1055 // RETURNS TRUE if a better gas is available
+ − 1056 //
+ − 1057 static unsigned char gas_find_better(void)
+ − 1058 {
+ − 1059 overlay unsigned char switch_depth = 255;
+ − 1060 overlay unsigned char switch_gas = 0;
+ − 1061 overlay unsigned char j;
+ − 1062
+ − 1063
+ − 1064 // no automatic gas changes in CCR mode and - as of now - in pSCR mode
+ − 1065 if( char_O_deco_status & DECO_MODE_LOOP ) return 0;
+ − 1066
+ − 1067 // Loop over all deco gases to find the shallowest one below or at current depth.
+ − 1068 for(j=0; j<NUM_GAS; ++j)
+ − 1069 {
+ − 1070 // Is this the gas we are already breathing?
+ − 1071 // If yes, skip this gas.
+ − 1072 if( j+1 == sim_gas_last_used ) continue;
+ − 1073
+ − 1074 // Is the change depth of the gas shallower than the current depth?
+ − 1075 // If yes, skip this gas as it is not to be used yet.
+ − 1076 // Remark: this check will also skip all disabled gases and the gas set
+ − 1077 // as 'first' because these have their change depth set to 0.
+ − 1078 if( temp_depth_limit > char_I_deco_gas_change[j] ) continue;
+ − 1079
+ − 1080 // Is the change depth of the gas deeper than the change depth of the
+ − 1081 // gas we are currently one?
+ − 1082 // If yes, skip this gas as it is not better than the current one.
+ − 1083 // Remark: if there is more than one gas with the same change depth,
+ − 1084 // the last one from the list will be taken.
+ − 1085 if( sim_gas_last_depth && (char_I_deco_gas_change[j] > sim_gas_last_depth) ) continue;
+ − 1086
+ − 1087 // Is the change depth of the gas shallower or equal to the change depth
+ − 1088 // of the best gas found so far, or is it the first better gas found?
+ − 1089 // If yes, we have a better gas
+ − 1090 if( char_I_deco_gas_change[j] <= switch_depth )
+ − 1091 {
+ − 1092 switch_gas = j+1; // remember this gas (1..5)
+ − 1093 switch_depth = char_I_deco_gas_change[j]; // remember its change depth
+ − 1094 }
+ − 1095 } // continue looping through all gases to eventually find an even better gas
+ − 1096
+ − 1097 // has a better gas been found?
+ − 1098 if( switch_gas )
+ − 1099 {
+ − 1100 // yes
+ − 1101 sim_gas_last_used = switch_gas; // report the index of the better
+ − 1102 sim_gas_last_depth = switch_depth; // report its change depth
+ − 1103
+ − 1104 assert( sim_gas_last_depth < switch_depth );
+ − 1105
+ − 1106 return 1; // signal a better gas was found
+ − 1107 }
+ − 1108 else
+ − 1109 {
+ − 1110 return 0; // signal no better gas was found
+ − 1111 }
+ − 1112 }
+ − 1113
+ − 1114 //////////////////////////////////////////////////////////////////////////////
+ − 1115 // Set calc_N2/He/O2_ratios by sim_gas_last_used
+ − 1116 //
+ − 1117 // Input: sim_gas_last_used : index of gas to use
+ − 1118 // N2_ratio, He_ratio : if gas 0 = the manually set gas is in use
+ − 1119 //
+ − 1120 // Output: calc_N2_ratio, calc_He_ratio, calc_O2ratio
+ − 1121 //
+ − 1122 static void gas_switch_set(void)
+ − 1123 {
+ − 1124 assert( 0 <= sim_gas_last_used <= NUM_GAS );
+ − 1125
+ − 1126 if( sim_gas_last_used == 0 ) // Gas6 = manually set gas.
+ − 1127 {
+ − 1128 calc_O2_ratio = O2_ratio;
+ − 1129 calc_He_ratio = He_ratio;
+ − 1130 }
+ − 1131 else
+ − 1132 {
+ − 1133 calc_O2_ratio = char_I_deco_O2_ratio[sim_gas_last_used-1] * 0.01;
+ − 1134 calc_He_ratio = char_I_deco_He_ratio[sim_gas_last_used-1] * 0.01;
+ − 1135 }
+ − 1136
+ − 1137 calc_N2_ratio = 1.0 - calc_O2_ratio - calc_He_ratio;
+ − 1138
+ − 1139 assert( 0.0 <= calc_N2_ratio && calc_N2_ratio <= 0.95 );
+ − 1140 assert( 0.0 <= calc_He_ratio && calc_He_ratio <= 1.00 );
+ − 1141 assert( (calc_N2_ratio + calc_He_ratio) <= 1.00 );
+ − 1142 }
+ − 1143
+ − 1144 //////////////////////////////////////////////////////////////////////////////
+ − 1145 // Compute ppN2 and ppHe
+ − 1146 //
+ − 1147 // Input: calc_N2_ratio, calc_He_ratio : simulated gas mix.
+ − 1148 // temp_deco : simulated respiration pressure
+ − 1149 // float_deco_distance : safety factor
+ − 1150 // ppWater : water-vapor pressure inside respiratory tract
+ − 1151 //
+ − 1152 // Output: ppN2, ppHe.
+ − 1153 //
+ − 1154 static void sim_alveolar_presures(void)
+ − 1155 {
+ − 1156 overlay float deco_diluent = temp_deco;
+ − 1157
+ − 1158 // read ppO2 reported from sensors or by setpoint // TODO: can be deleted
+ − 1159 // char_actual_ppO2 = char_I_const_ppO2;
+ − 1160
+ − 1161
+ − 1162 // Take deco offset into account, but not at surface.
+ − 1163 // Note: this should be done on ambient pressure, hence before
+ − 1164 // computing the diluent partial pressure...
+ − 1165 if( deco_diluent > pres_surface ) deco_diluent += float_deco_distance;
+ − 1166
+ − 1167 if( char_O_deco_status & DECO_MODE_LOOP )
+ − 1168 {
+ − 1169 //---- Loop mode : adjust ppN2 and ppHe for change in ppO2 due to setpoint (CCR) or drop (pSCR)-------
+ − 1170
+ − 1171 // get current setpoint (CCR) or sensor value (CCR, for pSCR see text below) as default
+ − 1172 overlay float const_ppO2 = char_I_const_ppO2 * 0.01;
+ − 1173
+ − 1174 if( char_O_deco_status & DECO_MODE_PSCR )
+ − 1175 {
+ − 1176 //---- PSCR mode : compute loop gas ----------------------------------------
+ − 1177 //
+ − 1178 // As the ppO2 in the loop changes with water depth, we can not use the current
+ − 1179 // sensor value as with CCR mode, but need to compute the ppO2 for the given depth.
+ − 1180 // Then we continue with the CCR mode code which calculates the increases of ppN2
+ − 1181 // and ppH2 due to the reduction of the ppO2 in the loop. Essentially, diving a
+ − 1182 // PSCR is like diving a CCR with a setpoint lower than the ambient pressure x the
+ − 1183 // O2 fraction of the diluent would yield...
+ − 1184 //
+ − 1185
+ − 1186 // deco_diluent is 0.0 ... in bar
+ − 1187 // calc_O2_ratio is 0.0 ... 1 as factor
+ − 1188 // char_I_PSCR_drop is 0 ... 15 as %
+ − 1189 // char_I_PSCR_lungratio is 5 ... 20 as %
+ − 1190 // const_ppO2 is 0.0 ... in bar
+ − 1191
+ − 1192 const_ppO2 = (deco_diluent * calc_O2_ratio) - (1 - calc_O2_ratio) * 0.01 * char_I_PSCR_drop * char_I_PSCR_lungratio;
+ − 1193
+ − 1194 // capture failure condition
+ − 1195 if( const_ppO2 < 0.0 ) const_ppO2 = 0.0;
+ − 1196 }
+ − 1197 else
+ − 1198 {
+ − 1199
+ − 1200 //---- CCR mode ------------------------------------------------------------
+ − 1201
+ − 1202 // Limit the setpoint to the maximum physically possible ppO2. This prevents for
+ − 1203 // example calculating with a setpoint of 1.3 bar in only 2 meters of depth.
+ − 1204 // Additionally, if limiting occurs, the ppO2 can be further reduced to account
+ − 1205 // for residual inert gases by the user-adjustable setting char_I_cc_max_frac_o2.
+ − 1206
+ − 1207 if( const_ppO2 > deco_diluent ) // no ppWater subtracted here to give some margin for
+ − 1208 { // sensors delivering data a little bit over target
+ − 1209
+ − 1210 const_ppO2 = 0.01 * char_I_cc_max_frac_o2 * (deco_diluent - ppWater);
+ − 1211 }
+ − 1212 }
+ − 1213
+ − 1214 if ( const_ppO2 == 0.0 ) char_actual_ppO2 = 0;
+ − 1215 else if ( const_ppO2 > 2.545 ) char_actual_ppO2 = 255;
+ − 1216 else char_actual_ppO2 = (unsigned char)(const_ppO2*100 + 0.5);
+ − 1217
+ − 1218 // Note: ppO2 and ratios are known outside the lungs, so there is no ppWater in the equations below:
+ − 1219 deco_diluent -= const_ppO2;
+ − 1220 deco_diluent /= calc_N2_ratio + calc_He_ratio;
+ − 1221
+ − 1222 // capture all failure conditions, including div/0 in case diluent is pure O2
+ − 1223 if( (deco_diluent < 0.0) || (calc_O2_ratio > 99.5) )
+ − 1224 {
+ − 1225 deco_diluent = 0.0;
+ − 1226
+ − 1227 char_actual_ppO2 = (unsigned char)(temp_deco*100 + 0.5); // without float_deco_distance here as this situation
+ − 1228 // is likely to occur only at 6 meters or shallower
+ − 1229 }
+ − 1230 }
+ − 1231 else
+ − 1232 {
+ − 1233 //---- OC mode: char_actual_ppO2 will be needed for CNS calculation later --------------------------------
+ − 1234
+ − 1235 overlay float ppO2 = pres_respiration * calc_O2_ratio;
+ − 1236
+ − 1237 if ( ppO2 > 2.545 ) char_actual_ppO2 = 255;
+ − 1238 else char_actual_ppO2 = (unsigned char)(ppO2*100 + 0.5);
+ − 1239 }
+ − 1240
+ − 1241
+ − 1242 if( deco_diluent > ppWater )
+ − 1243 {
+ − 1244 ppN2 = calc_N2_ratio * (deco_diluent - ppWater);
+ − 1245 ppHe = calc_He_ratio * (deco_diluent - ppWater);
+ − 1246 }
+ − 1247 else
+ − 1248 {
+ − 1249 ppN2 = 0.0;
+ − 1250 ppHe = 0.0;
+ − 1251 }
+ − 1252
+ − 1253 assert( 0.0 <= ppN2 && ppN2 < 14.0 );
+ − 1254 assert( 0.0 <= ppHe && ppHe < 14.0 );
+ − 1255 }
+ − 1256
+ − 1257 //////////////////////////////////////////////////////////////////////////////
+ − 1258 // clear_tissue
+ − 1259 //
+ − 1260 // optimized in v.101 (var_N2_a)
+ − 1261 //
+ − 1262 // preload tissues with standard pressure for the given ambient pressure.
+ − 1263 // Note: fixed N2_ratio for standard air.
+ − 1264 //
+ − 1265 static void clear_tissue(void)
+ − 1266 {
+ − 1267 pres_respiration = 0.001 * int_I_pres_respiration;
+ − 1268 N2_equilibrium = 0.7902 * (pres_respiration - ppWater);
+ − 1269
+ − 1270 for(ci=0; ci<NUM_COMP; ci++)
+ − 1271 {
+ − 1272 // cycle through the 16 Buhlmann N2 tissues
+ − 1273 pres_tissue_N2[ci] = N2_equilibrium; // initialize data for "real" tissue
+ − 1274 char_O_tissue_N2_saturation[ci] = 11; // initialize data for tissue graphics
+ − 1275
+ − 1276
+ − 1277 // cycle through the 16 Buhlmann He tissues
+ − 1278 pres_tissue_He[ci] = 0.0; // initialize data for "real" tissue
+ − 1279 char_O_tissue_He_saturation[ci] = 0; // initialize data for tissue graphics
+ − 1280 }
+ − 1281
+ − 1282 clear_CNS_fraction();
+ − 1283
+ − 1284 clear_deco_table();
+ − 1285
+ − 1286 char_O_main_status = 0;
+ − 1287 char_O_deco_status = 0;
+ − 1288 char_O_nullzeit = 0;
+ − 1289 char_O_gtissue_no = 0;
+ − 1290 char_O_deco_warnings = 0;
+ − 1291
+ − 1292 int_O_ascenttime = 0;
+ − 1293 int_O_gradient_factor = 0;
+ − 1294
+ − 1295 calc_lead_tissue_limit = 0.0;
+ − 1296 }
+ − 1297
+ − 1298 //////////////////////////////////////////////////////////////////////////////
+ − 1299 // calc_hauptroutine
+ − 1300 //
+ − 1301 // this is the major code in dive mode calculates:
+ − 1302 // the tissues,
+ − 1303 // the bottom time,
+ − 1304 // and simulates the ascend with all deco stops.
+ − 1305 //
+ − 1306 //
+ − 1307 static void calc_hauptroutine(void)
+ − 1308 {
+ − 1309 unsigned int int_ppO2_min;
+ − 1310 unsigned int int_ppO2_max;
+ − 1311
+ − 1312
+ − 1313 //--- set-up part --------------------------------------------------------------------------------
+ − 1314
+ − 1315 // twosectimer:
+ − 1316 // calc_hauptroutine is now invoked every second to speed up the deco planning.
+ − 1317 // Because the tissue and CNS calculations are based on a 2 seconds period, the
+ − 1318 // the following toggle-timer will be used by the respective routines to skip
+ − 1319 // every 2nd invocation.
+ − 1320 twosectimer = (twosectimer) ? 0 : 1; // toggle the toggle-timer
+ − 1321
+ − 1322
+ − 1323 // set up normal tissue updating or "fast forward" updating for simulator sim+5' function
+ − 1324 // and deco calculator bottom time calculation
+ − 1325 if( char_I_sim_advance_time > 0 )
+ − 1326 {
+ − 1327 // configure char_I_sim_advance_time minutes of tissue updating
+ − 1328 tissue_increment = char_I_sim_advance_time // given number of minutes, limited to 127
+ − 1329 | 128; // set flag for updating the "real" tissues & CNS
+ − 1330
+ − 1331 char_I_sim_advance_time = 0; // clear "mailbox"
+ − 1332 }
+ − 1333 else
+ − 1334 {
+ − 1335 // configure 2 seconds of tissue updating
+ − 1336 tissue_increment = 0 // encoding for 2 seconds update
+ − 1337 | 128; // set flag for updating the "real" tissues & CNS
+ − 1338 }
+ − 1339
+ − 1340 //---- calculate the real tissue's data -----------------------------------------------------------------
+ − 1341
+ − 1342 calc_hauptroutine_data_input(); // acquire current environment data
+ − 1343
+ − 1344 calc_hauptroutine_update_tissues(); // update tissue pressures, also sets char_actual_ppO2
+ − 1345
+ − 1346 calc_CNS_fraction(); // calculate CNS% for the real tissues
+ − 1347
+ − 1348 compute_CNS_for_display(); // compute integer copy of CNS value for display purpose
+ − 1349
+ − 1350 calc_gradient_factor(); // compute current GF
+ − 1351
+ − 1352
+ − 1353 //---- compute ppO2 warnings ------------------------------------------------------------------------------
+ − 1354
+ − 1355 // compute conditional min/max values
+ − 1356 int_ppO2_min = (char_O_main_status & DECO_MODE_LOOP) ? (unsigned int)char_I_ppO2_min_loop : (unsigned int)char_I_ppO2_min;
+ − 1357 int_ppO2_max = (char_O_deco_warnings & DECO_FLAG ) ? (unsigned int)char_I_ppO2_max_deco : (unsigned int)char_I_ppO2_max;
+ − 1358
+ − 1359 // check for safe range of pure oxygen
+ − 1360 if ( int_O_O2_ppO2 >= int_ppO2_max ) int_O_O2_ppO2 |= INT_FLAG_WARNING + INT_FLAG_HIGH;
+ − 1361
+ − 1362 // check for safe range of breathed gas
+ − 1363 if ( int_O_breathed_ppO2 <= int_ppO2_min ) int_O_breathed_ppO2 |= INT_FLAG_WARNING + INT_FLAG_LOW;
+ − 1364 else if ( int_O_breathed_ppO2 >= int_ppO2_max ) int_O_breathed_ppO2 |= INT_FLAG_WARNING + INT_FLAG_HIGH;
+ − 1365 else if ( int_O_breathed_ppO2 >= ppO2_prewarn_threshold ) int_O_breathed_ppO2 |= INT_FLAG_PREWARNING;
+ − 1366
+ − 1367 // check for safe range of pure diluent
+ − 1368 if ( int_O_pure_ppO2 <= (unsigned int)char_I_ppO2_min ) int_O_pure_ppO2 |= INT_FLAG_WARNING + INT_FLAG_LOW;
+ − 1369 else if ( int_O_pure_ppO2 >= int_ppO2_max ) int_O_pure_ppO2 |= INT_FLAG_WARNING + INT_FLAG_HIGH;
+ − 1370
+ − 1371 // check for safe range of calculated pSCR loop gas
+ − 1372 if ( int_O_pSCR_ppO2 <= int_ppO2_min ) int_O_pSCR_ppO2 |= INT_FLAG_WARNING + INT_FLAG_LOW;
+ − 1373 else if ( int_O_pSCR_ppO2 >= int_ppO2_max ) int_O_pSCR_ppO2 |= INT_FLAG_WARNING + INT_FLAG_HIGH;
+ − 1374
+ − 1375
+ − 1376 //---- toggle between calculation for NDL (bottom time), deco stops and more deco stops (continue) ------
+ − 1377
+ − 1378 switch( char_O_deco_status & DECO_STATUS_MASK )
+ − 1379 {
+ − 1380 overlay unsigned char i;
+ − 1381
+ − 1382 case DECO_STATUS_INIT: //---- At surface: start a new dive ---------------------
+ − 1383
+ − 1384 clear_deco_table();
+ − 1385 copy_deco_table();
+ − 1386
+ − 1387 char_I_ascent_speed = 10; // DEBUG - remove before flight!
+ − 1388 char_I_gas_change_time = 1; // DEBUG - remove before flight!
+ − 1389
+ − 1390 float_ascent_speed = 1.00 * char_I_ascent_speed;
+ − 1391 float_desaturation_multiplier = 0.01 * char_I_desaturation_multiplier;
+ − 1392 float_saturation_multiplier = 0.01 * char_I_saturation_multiplier;
+ − 1393 float_deco_distance = 0.01 * char_I_deco_distance;
+ − 1394
+ − 1395 int_O_ascenttime = 0; // Reset ascent time in normal plan
+ − 1396 int_O_alternate_ascenttime = 0; // Reset ascent time in alternative plan
+ − 1397 char_O_nullzeit = 0; // Reset no decompression limit (NDL) in normal plan
+ − 1398 char_O_alternate_nullzeit = 0; // Reset no decompression limit (NDL) in alternative plan
+ − 1399 char_O_deco_warnings = 0; // Reset all deco warning flags
+ − 1400 deco_tissue_vector = 0; // Reset tissue deco vector
+ − 1401 IBCD_tissue_vector = 0; // Reset tissue IBCD vector
+ − 1402
+ − 1403 int_O_desaturation_time = 65535; // tag desaturation time as invalid (it will not be computed during a dive)
+ − 1404
+ − 1405
+ − 1406 for(i=0; i<NUM_GAS; ++i)
+ − 1407 {
+ − 1408 int_O_gas_volumes[i] = 0;
+ − 1409 int_O_tank_pres_need[i] = 0 + INT_FLAG_ZERO; // 0 bar + flag for 0 bar
+ − 1410 }
+ − 1411
+ − 1412 for(i=0; i<NUM_COMP; ++i)
+ − 1413 {
+ − 1414 split_N2_He[i] = 90; // used for calculation of no-fly time
+ − 1415 }
+ − 1416
+ − 1417
+ − 1418 // init CNS counters
+ − 1419 CNS_sim_norm_fraction = CNS_sim_alt_fraction = CNS_fraction; // the floats
+ − 1420 int_O_normal_CNS_fraction = int_O_alternate_CNS_fraction = int_O_CNS_fraction; // the integers
+ − 1421
+ − 1422
+ − 1423 // Values that should be reset just once for the full real dive.
+ − 1424 // This is used to record the lowest stop for the whole dive,
+ − 1425 // including ACCROSS all simulated ascents.
+ − 1426 low_depth_norm = low_depth_alt = 0.0;
+ − 1427 locked_GF_step_norm = locked_GF_step_alt = 0.0;
+ − 1428
+ − 1429
+ − 1430 // continue in state DECO_STATUS_START to calculate the bottom-part of the dive and the NDL
+ − 1431 char_O_deco_status &= ~DECO_STATUS_MASK;
+ − 1432
+ − 1433 // code execution continues in state DECO_STATUS_START
+ − 1434
+ − 1435
+ − 1436 case DECO_STATUS_START: //---- bottom time -------------------------------------
+ − 1437 default:
+ − 1438
+ − 1439 // reread the GF settings in case there was a switch between GF/aGF
+ − 1440 GF_low = char_I_GF_Low_percentage * 0.01;
+ − 1441 GF_high = char_I_GF_High_percentage * 0.01;
+ − 1442 GF_delta = GF_high - GF_low;
+ − 1443
+ − 1444 // Lookup current gas and store it also as the first gas used. This gas will be used for the bottom
+ − 1445 // segment of the dive and for the period of delayed ascent when calculating fTTS or bailout.
+ − 1446 gas_find_current();
+ − 1447
+ − 1448 // setup the calculation ratio's for N2, He and O2
+ − 1449 gas_switch_set();
+ − 1450
+ − 1451 // clear the internal(!) stops table
+ − 1452 clear_deco_table();
+ − 1453
+ − 1454 // initialize the simulated tissues with the current state of the real tissues
+ − 1455 update_startvalues();
+ − 1456
+ − 1457 // calculate the effect of extended bottom time due to delayed ascent / fTTS on current gas
+ − 1458 if( char_O_deco_status & DECO_ASCENT_DELAYED ) sim_extra_time();
+ − 1459
+ − 1460 // calculate if we are within no decompression limit (NDL)
+ − 1461 calc_nullzeit();
+ − 1462
+ − 1463 // check which plan we are on
+ − 1464 if( char_O_deco_status & DECO_PLAN_ALTERNATE )
+ − 1465 {
+ − 1466 // alternate dive plan
+ − 1467 if( char_O_alternate_nullzeit > 0 ) // Some NDL time left in alternate plan?
+ − 1468 {
+ − 1469 copy_deco_table(); // DEBUG to be removed again
+ − 1470
+ − 1471 // clear tank pressure needs
+ − 1472 if( char_O_deco_status & DECO_VOLUME_CALCULATE )
+ − 1473 for(i=0; i<NUM_GAS; ++i) int_O_tank_pres_need[i] = 0 + INT_FLAG_ZERO; // 0 bar + flag for 0 bar
+ − 1474
+ − 1475 // calculate the CNS% at the end of the dive if requested:
+ − 1476 // as we are in no stop, CNS at end of dive is more or less the same CNS we have now
+ − 1477 if( char_O_deco_status & DECO_CNS_CALCULATE ) int_O_alternate_CNS_fraction = int_O_CNS_fraction;
+ − 1478
+ − 1479 // clear fTTS ascent time
+ − 1480 int_O_alternate_ascenttime = 0;
+ − 1481
+ − 1482 char_O_deco_status &= ~DECO_STATUS_MASK; // YES: computation of alternate plan completed
+ − 1483 }
+ − 1484 else
+ − 1485 {
+ − 1486 char_O_deco_status &= ~DECO_STATUS_MASK; // NO: clear status bits and set status bits
+ − 1487 char_O_deco_status |= DECO_STATUS_ASCENT; // for calculation of ascent on next invocation
+ − 1488 }
+ − 1489 }
+ − 1490 else
+ − 1491 {
+ − 1492 // normal dive plan
+ − 1493 if( char_O_nullzeit > 0 ) // Some NDL time left in normal plan?
+ − 1494 {
+ − 1495 //copy_deco_table(); DEBUG original - comment in again // copy (erased) internal to external stops table
+ − 1496
+ − 1497 // commented out - char_O_deco_last_stop not used for anything
+ − 1498 // char_O_deco_last_stop = 0; // set last stop to 0 (for OSTC menu animation)
+ − 1499
+ − 1500 // clear tank pressure needs
+ − 1501 if( char_O_deco_status & DECO_VOLUME_CALCULATE )
+ − 1502 for(i=0; i<NUM_GAS; ++i) int_O_tank_pres_need[i] = 0 + INT_FLAG_ZERO; // 0 bar + flag for 0 bar
+ − 1503
+ − 1504 // calculate the CNS% at the end of the dive if requested:
+ − 1505 // as we are in no stop, CNS at end of dive is more or less the same CNS we have now
+ − 1506 if( char_O_deco_status & DECO_CNS_CALCULATE ) int_O_normal_CNS_fraction = int_O_CNS_fraction;
+ − 1507
+ − 1508 char_O_deco_status &= ~DECO_STATUS_MASK; // computation of normal plan completed
+ − 1509 }
+ − 1510 else
+ − 1511 {
+ − 1512 char_O_deco_status &= ~DECO_STATUS_MASK; // clear status bits and set status bits
+ − 1513 char_O_deco_status |= DECO_STATUS_ASCENT; // for calculation of ascent on next invocation
+ − 1514 }
+ − 1515 }
+ − 1516
+ − 1517 break;
+ − 1518
+ − 1519
+ − 1520 case DECO_STATUS_ASCENT: //---- Simulate ascent to first stop -------------------
+ − 1521
+ − 1522 // initialize depth (in abs.pressure) for ascent and deco simulation, start from current real depth
+ − 1523 temp_deco = pres_respiration;
+ − 1524
+ − 1525 // calculate ascent to first stop
+ − 1526 sim_ascent_to_first_stop();
+ − 1527
+ − 1528 // calculate all further stops next time
+ − 1529 char_O_deco_status &= ~DECO_STATUS_MASK; // clear status bits and set status bits
+ − 1530 char_O_deco_status |= DECO_STATUS_STOPS; // for calculation of stops on next invocation
+ − 1531
+ − 1532 break;
+ − 1533
+ − 1534
+ − 1535 case DECO_STATUS_STOPS: //---- Simulate stops ----------------------------------
+ − 1536
+ − 1537 calc_hauptroutine_calc_deco();
+ − 1538
+ − 1539 // If simulation is finished, do some more computations if requested
+ − 1540 // and restore the GF low reference so that the next ascent simulation
+ − 1541 // is done from the current depth:
+ − 1542 if( !(char_O_deco_status & DECO_STATUS_MASK) )
+ − 1543 {
+ − 1544 // Calculate ascent time, result in int_O_ascenttime or int_O_alternate_ascenttime
+ − 1545 calc_ascenttime();
+ − 1546
+ − 1547 // the current depth is needed by calc_CNS_planning() and gas_volumes()
+ − 1548 char_I_bottom_depth = (unsigned char)((pres_respiration - pres_surface)*BAR_TO_METER);
+ − 1549
+ − 1550 // if requested, calculate the CNS% at the end of the dive (including the deco stops)
+ − 1551 if( char_O_deco_status & DECO_CNS_CALCULATE ) calc_CNS_planning();
+ − 1552
+ − 1553 // if requested, calculate the required gas volumes and tank pressures at the end of the dive.
+ − 1554 if( char_O_deco_status & DECO_VOLUME_CALCULATE ) gas_volumes();
+ − 1555
+ − 1556 // some more aftermath dependent on the current plan
+ − 1557 if( char_O_deco_status & DECO_PLAN_ALTERNATE )
+ − 1558 {
+ − 1559 //---- alternative plan ----------------------------------------------------
+ − 1560
+ − 1561 copy_deco_table(); // DEBUG to be removed again
+ − 1562
+ − 1563 // was CNS at end of dive calculated?
+ − 1564 if( char_O_deco_status & DECO_CNS_CALCULATE )
+ − 1565 {
+ − 1566 // yes - compute CNS value to display
+ − 1567 if ( CNS_sim_alt_fraction < 0.01 ) int_O_alternate_CNS_fraction = 0;
+ − 1568 else if ( CNS_sim_alt_fraction > 9.985 ) int_O_alternate_CNS_fraction = 999 + INT_FLAG_WARNING;
+ − 1569 else
+ − 1570 {
+ − 1571 // convert float to integer
+ − 1572 int_O_alternate_CNS_fraction = (unsigned short)(100 * CNS_sim_alt_fraction + 0.5);
+ − 1573
+ − 1574 // set warning flag if CNS is >= 100%
+ − 1575 if( int_O_alternate_CNS_fraction >= 100 )
+ − 1576 int_O_alternate_CNS_fraction |= INT_FLAG_WARNING;
+ − 1577
+ − 1578 // set invalid flag if there is an overflow in the stops table
+ − 1579 if( char_O_deco_warnings & DECO_WARNING_STOPTABLE_OVERFLOW )
+ − 1580 int_O_alternate_CNS_fraction |= INT_FLAG_INVALID;
+ − 1581 }
+ − 1582 }
+ − 1583 else
+ − 1584 {
+ − 1585 // no - invalidate value (value = 0, invalid flag set)
+ − 1586 int_O_alternate_CNS_fraction = INT_FLAG_INVALID;
+ − 1587 }
+ − 1588 }
+ − 1589 else
+ − 1590 {
+ − 1591 //---- normal plan ---------------------------------------------------------
+ − 1592
+ − 1593 // publish the stops table
+ − 1594 // copy_deco_table(); // DEBUG original
+ − 1595
+ − 1596 // was CNS at end of dive calculated?
+ − 1597 if( char_O_deco_status & DECO_CNS_CALCULATE )
+ − 1598 {
+ − 1599 // yes - compute CNS value to display
+ − 1600 if ( CNS_sim_norm_fraction < 0.01 ) int_O_normal_CNS_fraction = 0;
+ − 1601 else if ( CNS_sim_norm_fraction >= 9.985 ) int_O_normal_CNS_fraction = 999 + INT_FLAG_WARNING;
+ − 1602 else
+ − 1603 {
+ − 1604 // convert float to integer
+ − 1605 int_O_normal_CNS_fraction = (unsigned short)(100 * CNS_sim_norm_fraction + 0.5);
+ − 1606
+ − 1607 // set warning flag if CNS is >= 100%
+ − 1608 if( int_O_normal_CNS_fraction >= 100 )
+ − 1609 int_O_normal_CNS_fraction |= INT_FLAG_WARNING;
+ − 1610
+ − 1611 // set invalid flag if there is an overflow in the stops table
+ − 1612 if( char_O_deco_warnings & DECO_WARNING_STOPTABLE_OVERFLOW )
+ − 1613 int_O_normal_CNS_fraction |= INT_FLAG_INVALID;
+ − 1614 }
+ − 1615 }
+ − 1616 else
+ − 1617 {
+ − 1618 // no - invalidate value (value = 0, invalid flag set)
+ − 1619 int_O_normal_CNS_fraction = INT_FLAG_INVALID;
+ − 1620 }
+ − 1621
+ − 1622 } // aftermath
+ − 1623 } // if
+ − 1624
+ − 1625 break;
+ − 1626
+ − 1627 } // switch
+ − 1628 }
+ − 1629
+ − 1630 //////////////////////////////////////////////////////////////////////////////
+ − 1631 // calc_hauptroutine_data_input
+ − 1632 //
+ − 1633 // Reset all C-code dive parameters from their ASM-code values.
+ − 1634 // Detect gas change condition.
+ − 1635 //
+ − 1636 void calc_hauptroutine_data_input(void)
+ − 1637 {
+ − 1638 // get the current pressures
+ − 1639 pres_respiration = 0.001 * int_I_pres_respiration;
+ − 1640 pres_surface = 0.001 * int_I_pres_surface;
+ − 1641
+ − 1642 // get the currently breathed gas mixture
+ − 1643 O2_ratio = 0.01 * char_I_O2_ratio;
+ − 1644 He_ratio = 0.01 * char_I_He_ratio;
+ − 1645
+ − 1646 // N2 ratios are computed within p2_deco.c from the O2 and He ratios
+ − 1647 N2_ratio = 1.0 - O2_ratio - He_ratio;
+ − 1648
+ − 1649 // N2 tissue pressure at surface equilibrium, used for tissue graphics scaling
+ − 1650 N2_equilibrium = 0.7902 * (pres_surface - ppWater);
+ − 1651 }
+ − 1652
+ − 1653 //////////////////////////////////////////////////////////////////////////////
+ − 1654 //
+ − 1655 //
+ − 1656 void calc_hauptroutine_update_tissues(void)
+ − 1657 {
+ − 1658 overlay float pres_diluent = pres_respiration;
+ − 1659
+ − 1660
+ − 1661 assert( 0.00 <= N2_ratio && N2_ratio <= 1.00 );
+ − 1662 assert( 0.00 <= He_ratio && He_ratio <= 1.00 );
+ − 1663 assert( (N2_ratio + He_ratio) <= 1.00 );
+ − 1664 assert( 0.800 < pres_respiration && pres_respiration < 14.0 );
+ − 1665
+ − 1666
+ − 1667 //---- OC, CCR and Bailout Mode Gas Calculations ------------------------------------------------------------
+ − 1668
+ − 1669 // calculate ppO2 of pure oxygen
+ − 1670 O2_ppO2 = (pres_respiration - ppWater);
+ − 1671
+ − 1672 // capture failure condition in case pres_respiration is < ppWater (should never happen...)
+ − 1673 if( O2_ppO2 < 0.0 ) O2_ppO2 = 0.0;
+ − 1674
+ − 1675 // calculate ppO2 of the pure gas (diluent)
+ − 1676 pure_ppO2 = O2_ppO2 * O2_ratio;
+ − 1677
+ − 1678
+ − 1679 //---- PSCR Mode Gas Calculation-----------------------------------------------------------
+ − 1680
+ − 1681 // With flags set for PSCR we compute the ppO2 in the loop from the diluent's O2
+ − 1682 // ratio and the PSCR parameters. This figure will be used in the pSCR custom view.
+ − 1683 // If sensors are used (char_I_const_ppO2 > 0), we will override the calculated ppO2
+ − 1684 // with the sensor data. Then we continue with the CCR mode code which calculates
+ − 1685 // the increase of ppN2 and ppH2 due to the reduction of the ppO2 in the loop.
+ − 1686 // Essentially, diving a pSCR is like diving a CCR with a setpoint set lower than
+ − 1687 // the ambient pressure multiplied with the O2 fraction of the diluent...
+ − 1688
+ − 1689 // calculate pSCR ppO2
+ − 1690 //
+ − 1691 // pres_respiration is 0.0 ... in bar
+ − 1692 // O2_ratio is 0.0 ... 1.0 as factor
+ − 1693 // char_I_PSCR_drop is 0 ... 15 as %
+ − 1694 // char_I_PSCR_lungratio is 5 ... 20 as %
+ − 1695 // pSCRppO2 is 0.0 ... in bar
+ − 1696
+ − 1697 pSCR_ppO2 = (pres_respiration * O2_ratio) - (1 - O2_ratio) * 0.01 * char_I_PSCR_drop * char_I_PSCR_lungratio;
+ − 1698
+ − 1699 // capture failure condition if case pSCR_ppO2 becomes negative
+ − 1700 if( pSCR_ppO2 < 0.0 ) pSCR_ppO2 = 0.0;
+ − 1701
+ − 1702
+ − 1703 //---- Loop modes : adjust ppN2 and ppHe for change in ppO2 due to setpoint (CCR) or drop (pSCR) ------------
+ − 1704 if ( char_O_main_status & DECO_MODE_LOOP )
+ − 1705 {
+ − 1706 overlay float const_ppO2;
+ − 1707
+ − 1708 // get the current sensor reading (CCR / pSCR if fitted) or the fixed setpoint (CCR) / a zero (pSCR)
+ − 1709 const_ppO2 = 0.01 * char_I_const_ppO2;
+ − 1710
+ − 1711 // Limit the setpoint to the maximum physically possible ppO2. This prevents for
+ − 1712 // example calculating with a setpoint of 1.3 bar in only 2 meters of depth.
+ − 1713 // Additionally, if limiting occurs, the ppO2 can be further reduced to account
+ − 1714 // for residual inert gases by the user-adjustable setting char_I_cc_max_frac_o2.
+ − 1715
+ − 1716 if( const_ppO2 > pres_respiration ) // no ppWater subtracted here to give some margin for
+ − 1717 { // sensors delivering data a little bit over target
+ − 1718
+ − 1719 const_ppO2 = 0.01 * char_I_cc_max_frac_o2 * (pres_respiration - ppWater);
+ − 1720 }
+ − 1721
+ − 1722 // check which kind of loop we are on
+ − 1723 if( char_O_main_status & DECO_MODE_PSCR )
+ − 1724 {
+ − 1725 //---- pSCR Mode --------------------------------------------------------------------------
+ − 1726
+ − 1727 // check if a sensor is fitted
+ − 1728 if( char_I_const_ppO2 ) breathed_ppO2 = const_ppO2; // yes - derive ppO2s from (char_I_)const_ppO2
+ − 1729 else breathed_ppO2 = pSCR_ppO2; // no - derive ppO2s from calculated ppO2
+ − 1730 }
+ − 1731 else
+ − 1732 {
+ − 1733 //---- CCR Mode ---------------------------------------------------------------------------
+ − 1734
+ − 1735 // derive breathed ppO2 from (char_I_)const_ppO2, which holds sensor reading or fixed setpoint
+ − 1736 breathed_ppO2 = const_ppO2;
+ − 1737 }
+ − 1738
+ − 1739 // adjust diluent pressure (ppN2 + ppHe) for change in ppO2 due to setpoint (CCR) or drop (pSCR)
+ − 1740 pres_diluent -= const_ppO2;
+ − 1741 pres_diluent /= N2_ratio + He_ratio;
+ − 1742
+ − 1743 // capture all failure conditions, including div/0 in case diluent is pure O2
+ − 1744 if( (pres_diluent < 0.0) || (char_I_O2_ratio == 100) )
+ − 1745 {
+ − 1746 pres_diluent = 0.0;
+ − 1747 breathed_ppO2 = pure_ppO2;
+ − 1748 }
+ − 1749
+ − 1750 }
+ − 1751 else
+ − 1752 { //---- OC mode -----------------------------------------------------------------------------------------
+ − 1753
+ − 1754 // breathed ppO2 is ppO2 of pure gas
+ − 1755 breathed_ppO2 = pure_ppO2;
+ − 1756 }
+ − 1757
+ − 1758
+ − 1759 // derive char_actual_ppO2 in [cbar], used for calculating CNS%
+ − 1760 if ( breathed_ppO2 < 0.01 ) char_actual_ppO2 = 0;
+ − 1761 else if ( breathed_ppO2 >= 2.545 ) char_actual_ppO2 = 255;
+ − 1762 else char_actual_ppO2 = (unsigned char)(100 * breathed_ppO2 + 0.5);
+ − 1763
+ − 1764
+ − 1765 //---- export ppO2 values in [cbar] for warning generation and display purpose ------------------------------
+ − 1766
+ − 1767 // pure oxygen ppO2
+ − 1768 if ( O2_ppO2 < 0.01 ) int_O_O2_ppO2 = 0;
+ − 1769 else if ( O2_ppO2 >= 9.995 ) int_O_O2_ppO2 = 999;
+ − 1770 else int_O_O2_ppO2 = (unsigned int)(100 * O2_ppO2 + 0.5);
+ − 1771
+ − 1772 // pure gas ppO2
+ − 1773 if ( pure_ppO2 < 0.01 ) int_O_pure_ppO2 = 0;
+ − 1774 else if ( pure_ppO2 >= 9.995 ) int_O_pure_ppO2 = 999;
+ − 1775 else int_O_pure_ppO2 = (unsigned int)(100 * pure_ppO2 + 0.5);
+ − 1776
+ − 1777 // calculated pSCR ppO2
+ − 1778 if ( pSCR_ppO2 < 0.01 ) int_O_pSCR_ppO2 = 0;
+ − 1779 else if ( pSCR_ppO2 >= 9.995 ) int_O_pSCR_ppO2 = 999;
+ − 1780 else int_O_pSCR_ppO2 = (unsigned int)(100 * pSCR_ppO2 + 0.5);
+ − 1781
+ − 1782 // breathed ppO2
+ − 1783 if ( breathed_ppO2 < 0.01 ) int_O_breathed_ppO2 = 0;
+ − 1784 else if ( breathed_ppO2 >= 9.995 ) int_O_breathed_ppO2 = 999;
+ − 1785 else int_O_breathed_ppO2 = (unsigned int)(100 * breathed_ppO2 + 0.5);
+ − 1786
+ − 1787
+ − 1788 //---- calculate ppN2, ppHe and EAD, END -------------------------------------------------------------------
+ − 1789
+ − 1790 if( pres_diluent > ppWater )
+ − 1791 {
+ − 1792 overlay float EAD, END;
+ − 1793
+ − 1794 ppN2 = N2_ratio * (pres_diluent - ppWater);
+ − 1795 ppHe = He_ratio * (pres_diluent - ppWater);
+ − 1796
+ − 1797 // EAD : Equivalent Air Depth. Equivalent depth for the same N2 level with plain air.
+ − 1798 // ppN2 = 79% * (P_EAD - ppWater)
+ − 1799 // EAD = (P_EAD - Psurface) * 10
+ − 1800 // ie: EAD = (ppN2 / 0.7902 + ppWater -Psurface) * 10
+ − 1801
+ − 1802 EAD = (ppN2 / 0.7902 + ppWater - pres_surface) * BAR_TO_METER;
+ − 1803
+ − 1804 if( (EAD < 0.0) || (EAD > 245.5) ) EAD = 0.0;
+ − 1805
+ − 1806 char_O_EAD = (unsigned char)(EAD + 0.5);
+ − 1807
+ − 1808
+ − 1809 // END : Equivalent Narcotic Depth.
+ − 1810 // Here we count O2 as narcotic too. Hence everything but helium (has a narcosis
+ − 1811 // factor of 0.23 btw). Hence the formula becomes:
+ − 1812 // END * BarPerMeter * (1.0 - 0.0) - ppWater + Psurface == Pambient - ppHe - ppWater
+ − 1813 // ie: END = (Pambient - ppHe - Psurface) * BAR_TO_METER
+ − 1814 //
+ − 1815 // Source cited:
+ − 1816 // The Physiology and Medicine of Diving by Peter Bennett and David Elliott,
+ − 1817 // 4th edition, 1993, W.B.Saunders Company Ltd, London.
+ − 1818
+ − 1819 END = (pres_respiration - ppHe - pres_surface) * BAR_TO_METER;
+ − 1820
+ − 1821 if( (END < 0.0) || (END > 245.5) ) END = 0.0;
+ − 1822
+ − 1823 char_O_END = (unsigned char)(END + 0.5);
+ − 1824 }
+ − 1825 else
+ − 1826 {
+ − 1827 ppN2 = ppHe = 0.0;
+ − 1828
+ − 1829 char_O_EAD = char_O_END = 0;
+ − 1830 }
+ − 1831
+ − 1832
+ − 1833 //---- calculate decompression status ----------------------------------------------------------------------
+ − 1834
+ − 1835 // Calculate tissues
+ − 1836 calc_tissue();
+ − 1837
+ − 1838 // Calculate limit for surface, ie. GF_high.
+ − 1839 calc_limit();
+ − 1840
+ − 1841
+ − 1842 // Fill int_O_ceiling (in mbar) if ceiling is below the surface
+ − 1843 if( (calc_lead_tissue_limit - pres_surface) > 0 )
+ − 1844 {
+ − 1845
+ − 1846 // compatibility version
+ − 1847 int_O_ceiling = (short)((calc_lead_tissue_limit - pres_surface) * 1000);
+ − 1848
+ − 1849 // new version
+ − 1850 // // Round up to next 10 cm so that the ceiling disappears on the display only when the ceiling
+ − 1851 // // limit is really zero. This will coincident then with TTS switching back to NDL time.
+ − 1852 // int_O_ceiling = (short)((calc_lead_tissue_limit-pres_surface)*1000+9);
+ − 1853
+ − 1854
+ − 1855 // limit int_O_ceiling to 16000 mbar (150 m)
+ − 1856 if( int_O_ceiling > 16000) int_O_ceiling = 16000;
+ − 1857 }
+ − 1858 else
+ − 1859 {
+ − 1860 int_O_ceiling = 0;
+ − 1861 }
+ − 1862
+ − 1863 int_O_gtissue_press = (short)((pres_tissue_N2[char_O_gtissue_no] + pres_tissue_He[char_O_gtissue_no]) * 1000);
+ − 1864 }
+ − 1865
+ − 1866
+ − 1867 //////////////////////////////////////////////////////////////////////////////
+ − 1868 // Compute stops.
+ − 1869 //
+ − 1870 // Note: because this can be very long, break on 16 iterations, and set state
+ − 1871 // to DECO_STATUS_FINISHED when finished, or to DECO_STATUS_STOPS when
+ − 1872 // needing to continue.
+ − 1873 // Note: because each iteration might be very long too (~ 66 ms in 1.84beta),
+ − 1874 // break the loop when elapsed time exceeds 512 milliseconds.
+ − 1875 //
+ − 1876 void calc_hauptroutine_calc_deco(void)
+ − 1877 {
+ − 1878 overlay unsigned char loop;
+ − 1879
+ − 1880 for(loop = 0; loop < 16; ++loop)
+ − 1881 {
+ − 1882 // limit loops to 512ms, using timer 5
+ − 1883 if( tmr5() & (512*32) ) break;
+ − 1884
+ − 1885 // calc_nextdecodepth()
+ − 1886 //
+ − 1887 // INPUT temp_deco : current depth in absolute pressure
+ − 1888 // OUTPUT temp_depth_limit : depth of next stop in meters
+ − 1889 // RETURN true if a stop is needed
+ − 1890 //
+ − 1891 // The function manages gas changes by itself, including priming
+ − 1892 // the deco stop with the configured gas change time.
+ − 1893 //
+ − 1894 if( calc_nextdecodepth() )
+ − 1895 {
+ − 1896 if( temp_depth_limit == 0 ) goto Surface; // this check should not bee needed as in
+ − 1897 // this case the RETURN value will be false
+ − 1898
+ − 1899 //---- stop required at temp_depth_limit -------------------------------------
+ − 1900
+ − 1901 // convert stop depth in meters to absolute pressure
+ − 1902 temp_deco = temp_depth_limit * METER_TO_BAR + pres_surface;
+ − 1903
+ − 1904 // add one minute to the current stop, or add a new stop,
+ − 1905 // or abort deco calculation if the deco table is full.
+ − 1906 if( !update_deco_table(1) ) goto Surface;
+ − 1907 }
+ − 1908 else
+ − 1909 {
+ − 1910 //---- no stop required --------------------------------------
+ − 1911
+ − 1912 // ascend by float_ascent_speed for 1 minute
+ − 1913 temp_deco -= float_ascent_speed * METER_TO_BAR;
+ − 1914
+ − 1915 // finish deco calculation if surface is reached
+ − 1916 if( temp_deco <= pres_surface )
+ − 1917 {
+ − 1918 Surface:
+ − 1919 // set deco engine status to done (DECO_STATUS_FINISHED)
+ − 1920 char_O_deco_status &= ~DECO_STATUS_MASK;
+ − 1921
+ − 1922 // commented out - char_O_deco_last_stop not used for anything
+ − 1923 // surface reached (to animate menu)
+ − 1924 // if( !(char_O_deco_status & DECO_PLAN_ALTERNATE)) char_O_deco_last_stop = 0;
+ − 1925
+ − 1926 return;
+ − 1927 }
+ − 1928 }
+ − 1929
+ − 1930
+ − 1931 //---- as one minute as passed now, update the tissues ----------------------
+ − 1932
+ − 1933 // program 1 minute interval on simulated tissues (Flagbit 7 = 0)
+ − 1934 tissue_increment = 1;
+ − 1935
+ − 1936 // compute current ppN2 and ppHe
+ − 1937 sim_alveolar_presures();
+ − 1938
+ − 1939 // update the tissues
+ − 1940 calc_tissue();
+ − 1941 }
+ − 1942
+ − 1943 // commented out - char_O_deco_last_stop not used for anything
+ − 1944 // surface not reached, need more stops... store reached depth for menu animation.
+ − 1945 // if( !(char_O_deco_status & DECO_PLAN_ALTERNATE) ) char_O_deco_last_stop = temp_depth_limit;
+ − 1946 }
+ − 1947
+ − 1948
+ − 1949 //////////////////////////////////////////////////////////////////////////////
+ − 1950 // Simulate ascent to first deco stop.
+ − 1951 //
+ − 1952 //
+ − 1953 // Modified: temp_deco : current depth in ascent and deco simulation, in bar absolute pressure
+ − 1954 //
+ − 1955 void sim_ascent_to_first_stop(void)
+ − 1956 {
+ − 1957 overlay unsigned char fast = 1; // 1 = 1 minute steps, 0 = 2 seconds steps
+ − 1958 overlay unsigned char gaschange = 0; // 1 = do a gas change, 0 = no better gas available
+ − 1959
+ − 1960
+ − 1961 //---- Loop until first deco stop or surface is reached ----------
+ − 1962 for(;;)
+ − 1963 {
+ − 1964 // depth in absolute pressure we came from
+ − 1965 overlay float old_deco = temp_deco;
+ − 1966
+ − 1967 // try ascending 1 full minute (fast) or 2 seconds (!fast)
+ − 1968 if ( fast ) temp_deco -= float_ascent_speed * METER_TO_BAR; // 1 min at float_ascent_speed ( 5 .. 10 m/min)
+ − 1969 else temp_deco -= (float_ascent_speed/30.0) * METER_TO_BAR; // 2 sec at float_ascent_speed (17 .. 33 cm/min)
+ − 1970
+ − 1971 // but don't go over surface
+ − 1972 if( temp_deco < pres_surface ) temp_deco = pres_surface;
+ − 1973
+ − 1974 // compute sim_lead_tissue_limit
+ − 1975 if ( char_I_deco_model != 0 ) sim_limit(GF_low);
+ − 1976 else sim_limit(1.0);
+ − 1977
+ − 1978 // did we overshoot the first deco stop?
+ − 1979 if( temp_deco < sim_lead_tissue_limit )
+ − 1980 {
+ − 1981 // YES - back to last depth below first stop
+ − 1982 temp_deco = old_deco;
+ − 1983
+ − 1984 // switch to 2 seconds ascent if not yet in, else done
+ − 1985 if( fast )
+ − 1986 {
+ − 1987 fast = 0; // retry with 2 seconds ascent steps
+ − 1988 continue;
+ − 1989 }
+ − 1990 else
+ − 1991 {
+ − 1992 break; // done...
+ − 1993 }
+ − 1994 }
+ − 1995
+ − 1996 // If code execution passes along here, we did not overshoot the first stop.
+ − 1997
+ − 1998 // did we reach the surface? if yes, done!
+ − 1999 if( temp_deco == pres_surface ) break;
+ − 2000
+ − 2001 // depth in meters where we are now (no round-up)
+ − 2002 temp_depth_limit = (unsigned char)((temp_deco - pres_surface) * BAR_TO_METER);
+ − 2003
+ − 2004 // Check if there is a better gas to switch to, but only in alternative plan mode.
+ − 2005 // If yes, introduce a stop for the gas change.
+ − 2006 if( (char_O_deco_status & DECO_PLAN_ALTERNATE) && gas_find_better() )
+ − 2007 {
+ − 2008 // depth in meters we came from
+ − 2009 overlay unsigned char old_depth_limit = (unsigned char)((old_deco - pres_surface) * BAR_TO_METER);
+ − 2010
+ − 2011 // adjust temp_depth_limit to the gas change depth, but not deeper than the depth we came from
+ − 2012 temp_depth_limit = (sim_gas_last_depth < old_depth_limit) ? sim_gas_last_depth : old_depth_limit;
+ − 2013
+ − 2014 // create a stop for the gas change
+ − 2015 update_deco_table(char_I_gas_change_time);
+ − 2016
+ − 2017 // set the new calculation values for N2, He and O2
+ − 2018 gas_switch_set();
+ − 2019
+ − 2020 // signal to create a stop for the gas change and update the tissues
+ − 2021 gaschange = char_I_gas_change_time;
+ − 2022
+ − 2023 // Adjust the depth for the tissue update to the stop depth. In case of fast mode, this
+ − 2024 // imposes that the ascent from the 'old_deco' depth to this stop took 1 minute although
+ − 2025 // we might have only ascended one or two meters...
+ − 2026 temp_deco = temp_depth_limit * METER_TO_BAR + pres_surface;
+ − 2027 }
+ − 2028
+ − 2029 // Did one minute pass by and/or do we have a gas change?
+ − 2030 // Remark: The 2 seconds ascent iterations towards the first deco stop in !fast speed may take
+ − 2031 // up to 28 seconds in total - for this rough half of a minute no tissue updates will be computed.
+ − 2032 // Well, it could be done by setting tissue_increment = 0 in !fast condition and making calls to
+ − 2033 // sim_alveolar_presures() and calc_tissue() - see code commented out.
+ − 2034 if( fast || gaschange )
+ − 2035 {
+ − 2036 // program interval on simulated tissues (flag bit 7 = 0)
+ − 2037 tissue_increment = fast + gaschange;
+ − 2038
+ − 2039 // clear gas change signal
+ − 2040 gaschange = 0;
+ − 2041 // }
+ − 2042 // else
+ − 2043 // {
+ − 2044 // // program 2 seconds interval on simulated tissues (flag bit 7 = 0)
+ − 2045 // tissue_increment = 0;
+ − 2046 // }
+ − 2047 // {
+ − 2048 // compute ppN2/ppHe for current depth from temp_deco
+ − 2049 sim_alveolar_presures();
+ − 2050
+ − 2051 // update the tissues
+ − 2052 calc_tissue();
+ − 2053 }
+ − 2054 }
+ − 2055 }
+ − 2056
+ − 2057 //////////////////////////////////////////////////////////////////////////////
+ − 2058 // Simulate extra time at the current depth.
+ − 2059 //
+ − 2060 // This routine is used for the futureTTS / delayed ascent feature.
+ − 2061 //
+ − 2062 void sim_extra_time(void)
+ − 2063 {
+ − 2064 overlay unsigned char backup = tissue_increment; // back-up tissue_increment
+ − 2065
+ − 2066 tissue_increment = char_I_extra_time; // program interval on simulated tissues (Flagbit 7 = 0)
+ − 2067
+ − 2068 calc_tissue(); // update the tissues
+ − 2069
+ − 2070 tissue_increment = backup; // restore tissue_increment
+ − 2071 }
+ − 2072
+ − 2073 //////////////////////////////////////////////////////////////////////////////
+ − 2074 // calc_tissue
+ − 2075 //
+ − 2076 // optimized in v.101
+ − 2077 //
+ − 2078 // INPUT: ppN2, ppHe, tissue_increment
+ − 2079 // MODIFIED: pres_tissue_N2[], pres_tissue_He[]
+ − 2080 // OUTPUT: char_O_tissue_N2_saturation[], char_O_tissue_He_saturation[]
+ − 2081 //
+ − 2082 static void calc_tissue()
+ − 2083 {
+ − 2084 overlay float temp_tissue_N2;
+ − 2085 overlay float temp_tissue_He;
+ − 2086 overlay unsigned char period;
+ − 2087 overlay unsigned char i;
+ − 2088
+ − 2089
+ − 2090 assert( 0.00 <= ppN2 && ppN2 < 11.2 ); // 80% N2 at 130m
+ − 2091 assert( 0.00 <= ppHe && ppHe < 12.6 ); // 90% He at 130m
+ − 2092
+ − 2093
+ − 2094 for (ci=0;ci<NUM_COMP;ci++) // iterate through all compartments
+ − 2095 {
+ − 2096 i = tissue_increment & 127; // extract number of minutes to do (if i > 0)
+ − 2097 // or if one 2 second period is to do (if i = 0)
+ − 2098
+ − 2099 if( i == 0 ) // check if we shall do one 2-seconds period
+ − 2100 {
+ − 2101 read_Buhlmann_times(0); // YES, program coefficients for a 2 seconds period
+ − 2102 period = 1; // set period length (in cycles)
+ − 2103 i = 1; // and one cycle to do
+ − 2104 }
+ − 2105 else if( i > 9 ) // check if we can start with 10 minutes periods
+ − 2106 {
+ − 2107 read_Buhlmann_times(2); // YES, program coefficients for 10 minutes periods
+ − 2108 period = 10; // set period length (in cycles) to ten
+ − 2109 }
+ − 2110 else // we shall do 1 to 9 minutes
+ − 2111 {
+ − 2112 read_Buhlmann_times(1); // program coefficients for 1 minute periods
+ − 2113 period = 1; // set period length (in cycles) to one
+ − 2114 }
+ − 2115
+ − 2116 do
+ − 2117 {
+ − 2118 //---- N2 -------------------------------------------------------------------------------
+ − 2119
+ − 2120 temp_tissue = (tissue_increment & 128) ? pres_tissue_N2[ci] : sim_pres_tissue_N2[ci];
+ − 2121
+ − 2122 temp_tissue = (ppN2 - temp_tissue) * var_N2_e;
+ − 2123
+ − 2124 temp_tissue_safety();
+ − 2125
+ − 2126 if( tissue_increment & 128 )
+ − 2127 {
+ − 2128 // The temp variable takes on purpose just the tissue increment from the last loop's iteration.
+ − 2129 temp_tissue_N2 = temp_tissue;
+ − 2130
+ − 2131 // Update the real tissues if either we are on the 2 seconds interval,
+ − 2132 // or if we shall advance the tissues on a one or several minutes basis.
+ − 2133 if( twosectimer || (tissue_increment & 127) ) pres_tissue_N2[ci] += temp_tissue;
+ − 2134 }
+ − 2135 else
+ − 2136 {
+ − 2137 // Updates of the sim-tissues always comes on a 1 minutes basis,
+ − 2138 // so we do not need to check of the 2 seconds interval.
+ − 2139 sim_pres_tissue_N2[ci] += temp_tissue;
+ − 2140 }
+ − 2141
+ − 2142
+ − 2143 //---- He -------------------------------------------------------------------------------
+ − 2144
+ − 2145 temp_tissue = (tissue_increment & 128) ? pres_tissue_He[ci] : sim_pres_tissue_He[ci];
+ − 2146
+ − 2147 temp_tissue = (ppHe - temp_tissue) * var_He_e;
+ − 2148
+ − 2149 temp_tissue_safety();
+ − 2150
+ − 2151 if( tissue_increment & 128 )
+ − 2152 {
+ − 2153 // The temp variable takes on purpose just the tissue increment from the last loop's iteration.
+ − 2154 temp_tissue_He = temp_tissue;
+ − 2155
+ − 2156 // Update the real tissues if either we are on the 2 seconds interval,
+ − 2157 // or if we shall advance the tissues on a one or several minutes basis.
+ − 2158 if( twosectimer || (tissue_increment & 127) ) pres_tissue_He[ci] += temp_tissue;
+ − 2159
+ − 2160 }
+ − 2161 else
+ − 2162 {
+ − 2163 // Updates of the sim-tissues always comes on a 1 minutes basis,
+ − 2164 // so we do not need to check of the 2 seconds interval.
+ − 2165 sim_pres_tissue_He[ci] += temp_tissue;
+ − 2166 }
+ − 2167
+ − 2168
+ − 2169 // decrement loop counter
+ − 2170 i -= period;
+ − 2171
+ − 2172 // check if we need to switch from 10 minute periods to 1 minute periods
+ − 2173 if( (i > 0) && (period = 10) && (i < 10) )
+ − 2174 {
+ − 2175 read_Buhlmann_times(1); // program coefficients for 1 minute periods
+ − 2176 period = 1; // set period length (in cycles) to one
+ − 2177 }
+ − 2178 }
+ − 2179 while( i );
+ − 2180
+ − 2181
+ − 2182 // have the computations been done for the "real" tissues?
+ − 2183 if( (tissue_increment & 128) && (twosectimer || (tissue_increment & 127)) )
+ − 2184 {
+ − 2185 // net tissue balance
+ − 2186 temp_tissue = temp_tissue_N2 + temp_tissue_He;
+ − 2187
+ − 2188 // check tissue on-/off-gassing and IBCD with applying a threshold of +/-HYST
+ − 2189 //
+ − 2190 if ( temp_tissue < -HYST ) // Check if the tissue is off-gassing
+ − 2191 {
+ − 2192 deco_tissue_vector |= (1 << ci); // tag tissue as being in decompression
+ − 2193 IBCD_tissue_vector &= ~(1 << ci); // tag tissue as not experiencing mentionable IBCD
+ − 2194 }
+ − 2195 else if ( temp_tissue > +HYST ) // check if the tissue in on-gassing
+ − 2196 {
+ − 2197 deco_tissue_vector &= ~(1 << ci); // tag tissue as not being in decompression
+ − 2198
+ − 2199 if( ((temp_tissue_N2 > 0.0) && (temp_tissue_He < 0.0)) // check for counter diffusion
+ − 2200 || ((temp_tissue_N2 < 0.0) && (temp_tissue_He > 0.0)) )
+ − 2201 {
+ − 2202 IBCD_tissue_vector |= (1 << ci); // tag tissue as experiencing mentionable IBCD
+ − 2203 }
+ − 2204 }
+ − 2205
+ − 2206
+ − 2207 // keep the saturating / desaturating flags from last invocation
+ − 2208 char_O_tissue_N2_saturation[ci] &= 128;
+ − 2209 char_O_tissue_He_saturation[ci] &= 128;
+ − 2210
+ − 2211 // flip the flags applying a hysteresis of HYST (actual value: see #define of HYST)
+ − 2212 if( temp_tissue_N2 > +HYST ) char_O_tissue_N2_saturation[ci] = 128; // set flag for tissue pressure is increasing
+ − 2213 else if( temp_tissue_N2 < -HYST ) char_O_tissue_N2_saturation[ci] = 0; // clear flag (-> tissue pressure is decreasing)
+ − 2214
+ − 2215 if( temp_tissue_He > +HYST ) char_O_tissue_He_saturation[ci] = 128; // set flag for tissue pressure is increasing
+ − 2216 else if( temp_tissue_He < -HYST ) char_O_tissue_He_saturation[ci] = 0; // clear flag (-> tissue pressure is decreasing)
+ − 2217
+ − 2218
+ − 2219 // For N2 tissue display purpose:
+ − 2220 // Scale tissue press so that saturation in 70m on AIR gives a value of approx. 80.
+ − 2221 // The surface steady-state tissue loading of [0.7902 * (pres_respiration - ppWater)] bar
+ − 2222 // gives then a 10. If N2 is completely washed out of the tissue, result will be 0.
+ − 2223 // This scaling is adapted to the capabilities of the tissue graphics in the custom views.
+ − 2224 temp_tissue = (pres_tissue_N2[ci] / N2_equilibrium) * 10;
+ − 2225
+ − 2226 // limit to 127 to leave space for sat/desat flag
+ − 2227 if (temp_tissue > 127) temp_tissue = 127;
+ − 2228
+ − 2229 // export as integer
+ − 2230 char_O_tissue_N2_saturation[ci] += (unsigned char)temp_tissue;
+ − 2231
+ − 2232
+ − 2233 // For H2 tissue display purpose:
+ − 2234 // Scale tissue press so that saturation in 120m on TMX 10/70 gives a value of approx. 70.
+ − 2235 // With no He in a tissue, result will be 0.
+ − 2236 // This scaling is adapted to the capabilities of the tissue graphics in the custom views.
+ − 2237 temp_tissue = pres_tissue_He[ci] * 7.7;
+ − 2238
+ − 2239 // limit to 127 to leave space for sat/desat flag
+ − 2240 if (temp_tissue > 127) temp_tissue = 127;
+ − 2241
+ − 2242 // export as integer
+ − 2243 char_O_tissue_He_saturation[ci] += (unsigned char)temp_tissue;
+ − 2244 }
+ − 2245
+ − 2246 }// for
+ − 2247 }
+ − 2248
+ − 2249 //////////////////////////////////////////////////////////////////////////////
+ − 2250 // calc_limit
+ − 2251 //
+ − 2252 // New in v.111 : separated from calc_tissue(), and depends on GF value.
+ − 2253 //
+ − 2254 static void calc_limit(void)
+ − 2255 {
+ − 2256 char_O_gtissue_no = 0;
+ − 2257 calc_lead_tissue_limit = 0.0;
+ − 2258
+ − 2259 // clear IBCD, microbubbles and outside warning flags (locked warnings will be preserved)
+ − 2260 char_O_deco_warnings &= ~(DECO_WARNING_IBCD + DECO_WARNING_MBUBBLES + DECO_WARNING_OUTSIDE);
+ − 2261
+ − 2262
+ − 2263 for(ci=0; ci<NUM_COMP; ci++)
+ − 2264 {
+ − 2265 overlay float N2 = pres_tissue_N2[ci];
+ − 2266 overlay float He = pres_tissue_He[ci];
+ − 2267 overlay float pres_tissue = N2 + He;
+ − 2268 overlay float pres_min;
+ − 2269 overlay float gf;
+ − 2270 overlay float threshold;
+ − 2271
+ − 2272 read_Buhlmann_coefficients();
+ − 2273 var_N2_a = (var_N2_a * N2 + var_He_a * He) / pres_tissue;
+ − 2274 var_N2_b = (var_N2_b * N2 + var_He_b * He) / pres_tissue;
+ − 2275
+ − 2276 // calculate minimum ambient pressure that the tissue can withstand according to straight Buhlmann
+ − 2277 pres_min = (pres_tissue - var_N2_a) * var_N2_b;
+ − 2278
+ − 2279 // calculate current gf value (1.0 = 100%) of this tissue
+ − 2280 gf = (pres_tissue - pres_respiration) / (pres_tissue - pres_min);
+ − 2281 if( gf < 0.0 ) gf = 0.0;
+ − 2282
+ − 2283 // calculate a threshold value for use below
+ − 2284 // ToDo: finalize the definition of the threshold
+ − 2285 threshold = 0.02 * ci + 0.9;
+ − 2286
+ − 2287 // check if this tissue is likely to develop microbubbles
+ − 2288 // and/or if this tissue is outside the Buhlmann model
+ − 2289 if( ci <= 5 )
+ − 2290 {
+ − 2291 if( gf >= threshold )
+ − 2292 {
+ − 2293 char_O_deco_warnings |= (DECO_WARNING_MBUBBLES + DECO_WARNING_MBUBBLES_lock);
+ − 2294
+ − 2295 if( gf >= 1.0 )
+ − 2296 {
+ − 2297 char_O_deco_warnings |= (DECO_WARNING_OUTSIDE + DECO_WARNING_OUTSIDE_lock);
+ − 2298 }
+ − 2299 }
+ − 2300 }
+ − 2301 else
+ − 2302 {
+ − 2303 if( gf >= 1.0 )
+ − 2304 {
+ − 2305 char_O_deco_warnings |= (DECO_WARNING_MBUBBLES + DECO_WARNING_MBUBBLES_lock);
+ − 2306
+ − 2307 if( gf >= threshold )
+ − 2308 {
+ − 2309 char_O_deco_warnings |= (DECO_WARNING_OUTSIDE + DECO_WARNING_OUTSIDE_lock);
+ − 2310 }
+ − 2311 }
+ − 2312 }
+ − 2313
+ − 2314
+ − 2315 // Apply the Eric Baker's varying gradient factor correction if the GF-Model is selected.
+ − 2316 // Note: the correction factor depends both on GF and b,
+ − 2317 // Actual values are in the 1.5 .. 1.0 range (for a GF=30%),
+ − 2318 // so that can change who is the leading gas...
+ − 2319 // Note: Also depends of the GF. So the calculus is different for GF_low, current GF, or GF_high...
+ − 2320 // *BUT* calc_tissue() is used to compute bottom time, hence what would happen at surface,
+ − 2321 // hence at GF_high.
+ − 2322 if( char_I_deco_model != 0 ) pres_min = ( pres_tissue - var_N2_a * ( GF_high) ) * var_N2_b
+ − 2323 / ( GF_high + var_N2_b * (1.0 - GF_high) );
+ − 2324
+ − 2325 // check if this tissue requires a higher ambient pressure than was found to be needed up to now
+ − 2326 if( pres_min > calc_lead_tissue_limit )
+ − 2327 {
+ − 2328 char_O_gtissue_no = ci;
+ − 2329 calc_lead_tissue_limit = pres_min;
+ − 2330 }
+ − 2331 }
+ − 2332
+ − 2333 // check IBCD condition
+ − 2334 if( !IBCD_tissue_vector )
+ − 2335 {
+ − 2336 char_O_deco_warnings &= ~DECO_WARNING_IBCD; // no IBCD in any tissue, clear flag
+ − 2337 }
+ − 2338 else if( (IBCD_tissue_vector & (1 << char_O_gtissue_no))
+ − 2339 && ((pres_tissue_N2[char_O_gtissue_no] + pres_tissue_He[char_O_gtissue_no]) > pres_respiration) )
+ − 2340 {
+ − 2341 // leading tissue is in IBCD condition and in super-saturation, set flags.
+ − 2342 char_O_deco_warnings |= (DECO_WARNING_IBCD + DECO_WARNING_IBCD_lock);
+ − 2343 }
+ − 2344
+ − 2345 // check if is any tissue off-gassing
+ − 2346 if (deco_tissue_vector) char_O_deco_warnings |= DECO_FLAG; // yes, set deco flag
+ − 2347 else char_O_deco_warnings &= ~DECO_FLAG; // no, clear deco flag
+ − 2348
+ − 2349
+ − 2350 assert( char_O_gtissue_no < NUM_COMP );
+ − 2351 assert( 0.0 <= calc_lead_tissue_limit && calc_lead_tissue_limit <= 14.0);
+ − 2352 }
+ − 2353
+ − 2354 //////////////////////////////////////////////////////////////////////////////
+ − 2355 // calc_nullzeit
+ − 2356 //
+ − 2357 // calculates the remaining bottom time
+ − 2358 //
+ − 2359 // NOTE: Erik Baker's closed formula works for Nitroxes. Trimix adds a second
+ − 2360 // exponential term to the M-value equation, making it impossible to
+ − 2361 // invert... So we have to make a fast-simu until we find a better way.
+ − 2362 //
+ − 2363 // Input: pres_respiration
+ − 2364 // Output: char_O_nullzeit / char_O_alternate_nullzeit
+ − 2365 //
+ − 2366 static void calc_nullzeit(void)
+ − 2367 {
+ − 2368 overlay unsigned char nullzeit = 240;
+ − 2369
+ − 2370
+ − 2371 //---- Compute ppN2 and ppHe ---------------------------------------------
+ − 2372 temp_deco = pres_respiration;
+ − 2373 sim_alveolar_presures();
+ − 2374
+ − 2375 for(ci=0; ci<NUM_COMP; ci++)
+ − 2376 {
+ − 2377 //---- Read A/B values and loading factor for N2 and He --------------
+ − 2378
+ − 2379 overlay float tN2 = sim_pres_tissue_N2[ci];
+ − 2380 overlay float tHe = sim_pres_tissue_He[ci];
+ − 2381
+ − 2382 overlay float t = tN2 + tHe;
+ − 2383 overlay unsigned char ndl;
+ − 2384 overlay unsigned char period = 10;
+ − 2385
+ − 2386 read_Buhlmann_coefficients();
+ − 2387 read_Buhlmann_times(2); // Starts with a 10min period.
+ − 2388
+ − 2389 //---- Simulate for that tissue --------------------------------------
+ − 2390 // NOTE: No need to simulate for longer than the already found NDL.
+ − 2391 for(ndl=0; ndl<nullzeit;)
+ − 2392 {
+ − 2393 //---- Compute updated mix M-value at surface
+ − 2394 overlay float a = (var_N2_a * tN2 + var_He_a * tHe) / t;
+ − 2395 overlay float b = (var_N2_b * tN2 + var_He_b * tHe) / t;
+ − 2396 overlay float M0 = (a + pres_surface/b);
+ − 2397
+ − 2398 //---- Add 10min/1min to N2/He tissues
+ − 2399 overlay float dTN2 = (ppN2 - tN2) * var_N2_e;
+ − 2400 overlay float dTHe = (ppHe - tHe) * var_He_e;
+ − 2401
+ − 2402 //---- Apply safety margin for both models
+ − 2403 // NDL can be computed while ascending... SO we have
+ − 2404 // to check if we are saturating or desaturating.
+ − 2405 if( dTN2 > 0.0 ) dTN2 *= float_saturation_multiplier;
+ − 2406 else dTN2 *= float_desaturation_multiplier;
+ − 2407
+ − 2408 if( dTHe > 0.0 ) dTHe *= float_saturation_multiplier;
+ − 2409 else dTHe *= float_saturation_multiplier;
+ − 2410
+ − 2411 // adopt M0 value when using the GF extension
+ − 2412 if (char_I_deco_model != 0 ) M0 = GF_high * (M0 - pres_surface) + pres_surface;
+ − 2413
+ − 2414 //---- Simulate off-gassing while going to surface
+ − 2415 // TODO !
+ − 2416 // dTN2 -= exp( ... ascent time ... ppN2...)
+ − 2417 // dTHe -= exp( ... ascent time ... ppHe...)
+ − 2418
+ − 2419 //---- Ok now, and still ok to surface after 1 or 10 minutes ?
+ − 2420 if( (t <= M0) && (t + dTN2 + dTHe <= M0) )
+ − 2421 {
+ − 2422 tN2 += dTN2; // YES: apply gas loadings,
+ − 2423 tHe += dTHe;
+ − 2424 t = tN2 + tHe;
+ − 2425
+ − 2426 ndl += period; // increment NDL,
+ − 2427
+ − 2428 continue; // and loop.
+ − 2429 }
+ − 2430
+ − 2431 //---- Should we retry with smaller steps ?
+ − 2432 if( period == 10 )
+ − 2433 {
+ − 2434 read_Buhlmann_times(1); // 1min coefs.
+ − 2435 period = 1;
+ − 2436
+ − 2437 continue;
+ − 2438 }
+ − 2439
+ − 2440 //---- ELSE make a linear approx for the last minute
+ − 2441 // Useful to have a meaningful rounding of NDL.
+ − 2442 // But ONLY if positive (negative casted to unsigned is bad).
+ − 2443 if( M0 > t ) ndl += (unsigned char)(0.5f + (M0-t)/(dTN2+dTHe));
+ − 2444
+ − 2445 break;
+ − 2446 }
+ − 2447
+ − 2448 // Keep the shortest NDL found
+ − 2449 if ( ndl < nullzeit ) nullzeit = ndl;
+ − 2450 }
+ − 2451
+ − 2452 if( char_O_deco_status & DECO_PLAN_ALTERNATE) char_O_alternate_nullzeit = nullzeit;
+ − 2453 else char_O_nullzeit = nullzeit;
+ − 2454 }
+ − 2455
+ − 2456 //////////////////////////////////////////////////////////////////////////////
+ − 2457 // calc_ascenttime
+ − 2458 //
+ − 2459 // Sum up ascent from bottom to surface at float_ascent_speed,
+ − 2460 // but 1 minute per meter for the final ascent, and all stops.
+ − 2461 //
+ − 2462 // Result in int_O_ascenttime,
+ − 2463 // or int_O_alternate_ascenttime if doing the alternative plan.
+ − 2464 //
+ − 2465 static void calc_ascenttime(void)
+ − 2466 {
+ − 2467 overlay unsigned char x;
+ − 2468 overlay unsigned short sum;
+ − 2469
+ − 2470 // preset final ascent
+ − 2471 overlay float final = (float)char_I_depth_last_deco;
+ − 2472
+ − 2473 // calculate depth
+ − 2474 overlay float ascent = (pres_respiration - pres_surface) * BAR_TO_METER;
+ − 2475
+ − 2476 // check if we are already in final ascent
+ − 2477 if (ascent <= final)
+ − 2478 {
+ − 2479 // yes - all ascent is final ascent
+ − 2480 final = ascent;
+ − 2481 ascent = 0.0;
+ − 2482 }
+ − 2483 else
+ − 2484 {
+ − 2485 // no - subtract final ascent part from overall ascent
+ − 2486 ascent -= final;
+ − 2487
+ − 2488 // compute time for ascent part without final ascent
+ − 2489 ascent /= float_ascent_speed;
+ − 2490 }
+ − 2491
+ − 2492 // add 1 minute for each meter of final ascent
+ − 2493 ascent += final;
+ − 2494
+ − 2495 // convert to integer
+ − 2496 sum = (unsigned short)(ascent + 0.5);
+ − 2497
+ − 2498 // add all stop times
+ − 2499 for(x=0; x<NUM_STOPS && internal_deco_depth[x]; x++)
+ − 2500 sum += (unsigned short)internal_deco_time[x];
+ − 2501
+ − 2502 // limit result to display max.
+ − 2503 if( sum > 999) sum = 999;
+ − 2504
+ − 2505 // tag result as invalid if there is an overflow in the stops table
+ − 2506 if( char_O_deco_warnings & DECO_WARNING_STOPTABLE_OVERFLOW ) sum |= INT_FLAG_INVALID;
+ − 2507
+ − 2508 // route result to output variable
+ − 2509 if( char_O_deco_status & DECO_PLAN_ALTERNATE ) int_O_alternate_ascenttime = sum;
+ − 2510 else int_O_ascenttime = sum;
+ − 2511 }
+ − 2512
+ − 2513 //////////////////////////////////////////////////////////////////////////////
+ − 2514 // update_startvalues
+ − 2515 //
+ − 2516 // updated in v.102
+ − 2517 //
+ − 2518 void update_startvalues(void)
+ − 2519 {
+ − 2520 overlay unsigned char x;
+ − 2521
+ − 2522 // Start ascent simulation with current tissue partial pressures.
+ − 2523 for(x=0; x<NUM_COMP; x++)
+ − 2524 {
+ − 2525 sim_pres_tissue_N2[x] = pres_tissue_N2[x];
+ − 2526 sim_pres_tissue_He[x] = pres_tissue_He[x];
+ − 2527 }
+ − 2528
+ − 2529 // No leading tissue (yet) for this ascent simulation.
+ − 2530 sim_lead_tissue_limit = 0.0;
+ − 2531 sim_lead_tissue_no = 1;
+ − 2532 }
+ − 2533
+ − 2534 //////////////////////////////////////////////////////////////////////////////
+ − 2535 // sim_limit()
+ − 2536 //
+ − 2537 // New in v.111
+ − 2538 //
+ − 2539 // Function separated from calc_tissue() to allow recomputing limit on
+ − 2540 // different depth, because it depends on current gradient factor.
+ − 2541 //
+ − 2542 static void sim_limit(PARAMETER float GF_current)
+ − 2543 {
+ − 2544 assert( 0.0 < GF_current && GF_current <= 1.0 );
+ − 2545
+ − 2546 sim_lead_tissue_limit = 0.0;
+ − 2547 sim_lead_tissue_no = 0; // If no one is critic, keep first tissue.
+ − 2548
+ − 2549 for(ci=0; ci<NUM_COMP; ci++)
+ − 2550 {
+ − 2551 overlay float N2 = sim_pres_tissue_N2[ci];
+ − 2552 overlay float He = sim_pres_tissue_He[ci];
+ − 2553 overlay float p = N2 + He;
+ − 2554
+ − 2555 read_Buhlmann_coefficients();
+ − 2556 var_N2_a = (var_N2_a * N2 + var_He_a * He) / p;
+ − 2557 var_N2_b = (var_N2_b * N2 + var_He_b * He) / p;
+ − 2558
+ − 2559 // Apply the Eric Baker's varying gradient factor correction.
+ − 2560 // Note: the correction factor depends both on GF and b,
+ − 2561 // Actual values are in the 1.5 .. 1.0 range (for a GF=30%),
+ − 2562 // so that can change who is the leading gas...
+ − 2563 // Note: Also depends of the GF_current...
+ − 2564 if( char_I_deco_model != 0 ) p = ( p - (var_N2_a * GF_current) )
+ − 2565 / ( 1.0 - GF_current + (GF_current / var_N2_b ) );
+ − 2566
+ − 2567 else p = (p - var_N2_a) * var_N2_b;
+ − 2568
+ − 2569
+ − 2570 if( p > sim_lead_tissue_limit )
+ − 2571 {
+ − 2572 sim_lead_tissue_no = ci;
+ − 2573 sim_lead_tissue_limit = p;
+ − 2574 }
+ − 2575 } // for ci
+ − 2576
+ − 2577 assert( sim_lead_tissue_no < NUM_COMP );
+ − 2578 assert( 0.0 <= sim_lead_tissue_limit && sim_lead_tissue_limit <= 14.0 );
+ − 2579 }
+ − 2580
+ − 2581 //////////////////////////////////////////////////////////////////////////////
+ − 2582 // clear_deco_table
+ − 2583 //
+ − 2584 //
+ − 2585 static void clear_deco_table(void)
+ − 2586 {
+ − 2587 overlay unsigned char x;
+ − 2588
+ − 2589 for(x=0; x<NUM_STOPS; ++x)
+ − 2590 {
+ − 2591 internal_deco_time [x] = 0;
+ − 2592 internal_deco_depth[x] = 0;
+ − 2593 }
+ − 2594
+ − 2595 // clear stop table overflow warning
+ − 2596 char_O_deco_warnings &= ~DECO_WARNING_STOPTABLE_OVERFLOW;
+ − 2597 }
+ − 2598
+ − 2599 //////////////////////////////////////////////////////////////////////////////
+ − 2600 // update_deco_table
+ − 2601 //
+ − 2602 // Add time to a stop at temp_depth_limit
+ − 2603 //
+ − 2604 // It is possible to create stops with a duration of 0 minutes, e.g. to
+ − 2605 // note a gas change "on the fly" while ascending. Therefore the criteria
+ − 2606 // to have reached the end of the list needs always to be depth == 0.
+ − 2607 //
+ − 2608 // Input: temp_depth_limit : stop's depth, in meters.
+ − 2609 // sim_gas_last_used : gas used at stop, as index 1..5
+ − 2610 // PARAMETER time_increment : number of minutes to add to the stop
+ − 2611 //
+ − 2612 // Updated: internal_deco_depth[] : depth (in meters) of each stop
+ − 2613 // internal_deco_time [] : time (in minutes) of each stop
+ − 2614 // internal_deco_gas [] : gas used (index 1-5) at each stop
+ − 2615 //
+ − 2616 static unsigned char update_deco_table(PARAMETER unsigned char time_increment)
+ − 2617 {
+ − 2618 overlay unsigned char x;
+ − 2619
+ − 2620 assert( temp_depth_limit > 0 ); // No stop at surface...
+ − 2621
+ − 2622 // loop through internal deco table
+ − 2623 for(x=0; x<NUM_STOPS; ++x)
+ − 2624 {
+ − 2625 // Make sure deco-stops are recorded in order:
+ − 2626 assert( !internal_deco_depth[x] || temp_depth_limit <= internal_deco_depth[x] );
+ − 2627
+ − 2628 // Is there already a stop entry for our current depth?
+ − 2629 if( internal_deco_depth[x] == temp_depth_limit )
+ − 2630 {
+ − 2631 // Yes - increment stop time if possible
+ − 2632 // Stop time entries are limited to 99 minutes because of display constraints.
+ − 2633 // Else a limit of 254 would account because of constrains in calc_CNS_planning().
+ − 2634 if( internal_deco_time[x] < (99 - time_increment) )
+ − 2635 {
+ − 2636 internal_deco_time[x] += time_increment; // increment stop time
+ − 2637 return 1; // return with status 'success'
+ − 2638 }
+ − 2639 }
+ − 2640
+ − 2641 // If program flow passes here, there is either no stop entry for the current depth yet, or
+ − 2642 // the existing entry is saturated with 99 minutes. So we are looking for the next unused
+ − 2643 // table entry.
+ − 2644 if( internal_deco_depth[x] == 0 )
+ − 2645 {
+ − 2646 internal_deco_time[x] = time_increment; // initialize entry with first stop's time,
+ − 2647 internal_deco_depth[x] = temp_depth_limit; // ... depth, and
+ − 2648 internal_deco_gas[x] = sim_gas_last_used; // ... gas
+ − 2649 return 1; // return with status 'success'
+ − 2650 }
+ − 2651 }
+ − 2652
+ − 2653 // If program flow passes here, all deco table entries are used up.
+ − 2654
+ − 2655 // set overflow warning
+ − 2656 char_O_deco_warnings |= DECO_WARNING_STOPTABLE_OVERFLOW;
+ − 2657
+ − 2658
+ − 2659 // return with status 'failed'.
+ − 2660 return 0;
+ − 2661 }
+ − 2662
+ − 2663 //////////////////////////////////////////////////////////////////////////////
+ − 2664 // calc_gradient_factor
+ − 2665 //
+ − 2666 // optimized in v.101 (var_N2_a)
+ − 2667 // new code in v.102
+ − 2668 //
+ − 2669 static void calc_gradient_factor(void)
+ − 2670 {
+ − 2671 overlay float gf;
+ − 2672 overlay float N2 = pres_tissue_N2[char_O_gtissue_no];
+ − 2673 overlay float He = pres_tissue_He[char_O_gtissue_no];
+ − 2674
+ − 2675 assert( char_O_gtissue_no < NUM_COMP );
+ − 2676 assert( 0.800 <= pres_respiration && pres_respiration < 14.0 );
+ − 2677
+ − 2678 // tissue > respiration (currently off-gassing)
+ − 2679 // GF = 0.00 when respiration == tissue, ie. dissolved gases are at equilibrium.
+ − 2680 // GF = 1.00 when respiration == limit.
+ − 2681 temp_tissue = N2 + He;
+ − 2682 if( temp_tissue <= pres_respiration )
+ − 2683 {
+ − 2684 gf = 0.0;
+ − 2685 int_O_gradient_factor = 0;
+ − 2686 }
+ − 2687 else
+ − 2688 {
+ − 2689 overlay float limit = calc_lead_tissue_limit;
+ − 2690 // NOTE: in GF model, calc_lead_tissue_limit include already the
+ − 2691 // correction due to gradient factor. To compute the actual
+ − 2692 // current GF, we need to (re-)compute the raw ambient-pressure
+ − 2693 // limit from the Buhlmann model.
+ − 2694 if( char_I_deco_model != 0 )
+ − 2695 {
+ − 2696 ci = char_O_gtissue_no;
+ − 2697
+ − 2698 read_Buhlmann_coefficients();
+ − 2699
+ − 2700 var_N2_a = (var_N2_a * N2 + var_He_a * He) / temp_tissue;
+ − 2701 var_N2_b = (var_N2_b * N2 + var_He_b * He) / temp_tissue;
+ − 2702
+ − 2703 limit = (temp_tissue - var_N2_a) * var_N2_b;
+ − 2704 }
+ − 2705
+ − 2706 gf = (temp_tissue - pres_respiration) / (temp_tissue - limit);
+ − 2707
+ − 2708 // limit to 255 because of constraints in ghostwriter code
+ − 2709 if ( gf <= 0.0 ) int_O_gradient_factor = 0;
+ − 2710 else if( gf > 2.545 ) int_O_gradient_factor = 255 + INT_FLAG_WARNING;
+ − 2711 else
+ − 2712 {
+ − 2713 int_O_gradient_factor = (unsigned int)(100 * gf + 0.5);
+ − 2714
+ − 2715 if ( int_O_gradient_factor >= GF_warning_threshold ) int_O_gradient_factor |= INT_FLAG_WARNING;
+ − 2716 else if ( int_O_gradient_factor >= GF_prewarning_threshold ) int_O_gradient_factor |= INT_FLAG_PREWARNING;
+ − 2717 }
+ − 2718 }
+ − 2719 }
+ − 2720
+ − 2721 //////////////////////////////////////////////////////////////////////////////
+ − 2722 // calc_desaturation_time
+ − 2723 //
+ − 2724 // FIXED N2_ratio
+ − 2725 // unchanged in v.101
+ − 2726 // Inputs: int_I_pres_surface, ppWater, char_I_desaturation_multiplier
+ − 2727 // Outputs: int_O_desaturation_time, int_O_nofly_time
+ − 2728 //
+ − 2729 // Helper function
+ − 2730 //
+ − 2731 void calc_desaturation_time_helper(void)
+ − 2732 {
+ − 2733 if( pres_actual > pres_target ) // check if actual pressure is higher then target pressure
+ − 2734 { // YES - compute remaining time
+ − 2735 overlay float pres_ratio;
+ − 2736
+ − 2737 pres_ratio = pres_actual / pres_target;
+ − 2738
+ − 2739 // Compute desaturation time with result rounded up to multiples of 10 minutes.
+ − 2740 // Main purpose is to avoid confusion, because the times do not clock down in one minute steps any more
+ − 2741 // but get constantly re-computed according to current ambient pressure and may therefor make steps of
+ − 2742 // several minutes forwards and backwards as ambient pressure rises and falls.
+ − 2743 short_time = (unsigned short)( (var_ht * log(pres_ratio) / desat_factor) + 0.9 );
+ − 2744 }
+ − 2745 else
+ − 2746 { // NO - desaturation state reached, no remaining time
+ − 2747 short_time = 0;
+ − 2748 }
+ − 2749 }
+ − 2750
+ − 2751 /////////////////////////////////////////////////////////////////////////////
+ − 2752 // Main function
+ − 2753 //
+ − 2754 void calc_desaturation_time(void)
+ − 2755 {
+ − 2756 assert( 800 < int_I_pres_surface && int_I_pres_surface < 1100 );
+ − 2757 assert( 0 < char_I_desaturation_multiplier && char_I_desaturation_multiplier <= 100 );
+ − 2758
+ − 2759
+ − 2760 N2_ratio = 0.7902; // fraction of N2 in respired air
+ − 2761 pres_surface = 0.001 * int_I_pres_surface; // surface pressure in bar
+ − 2762 N2_equilibrium = N2_ratio * (pres_surface - ppWater); // partial pressure of N2 in respired air
+ − 2763 desat_factor = 0.06931 * char_I_desaturation_multiplier * SURFACE_DESAT_FACTOR; // pre-computed term for later use:
+ − 2764 // 10 [Min] * 0.01 [%] * 0.6931 [ln(2)] * ...
+ − 2765 int_O_desaturation_time = 0;
+ − 2766 int_O_nofly_time = 0;
+ − 2767
+ − 2768
+ − 2769 for(ci=NUM_COMP; ci>0;)
+ − 2770 {
+ − 2771 overlay float pres_tissue_max;
+ − 2772 overlay float P_ambient_altitude;
+ − 2773 overlay signed char search_direction;
+ − 2774 overlay unsigned short nofly_N2 = 0;
+ − 2775 overlay unsigned short nofly_He = 0;
+ − 2776 overlay unsigned short nofly_last = ~0;
+ − 2777
+ − 2778
+ − 2779 ci -= 1;
+ − 2780
+ − 2781 read_Buhlmann_ht();
+ − 2782 read_Buhlmann_coefficients();
+ − 2783
+ − 2784 // get selected target altitude
+ − 2785 switch( char_I_altitude_wait )
+ − 2786 {
+ − 2787 case 1: P_ambient_altitude = P_ambient_1000m; break;
+ − 2788 case 2: P_ambient_altitude = P_ambient_2000m; break;
+ − 2789 case 3: P_ambient_altitude = P_ambient_3000m; break;
+ − 2790 default: P_ambient_altitude = P_ambient_fly; break;
+ − 2791 }
+ − 2792
+ − 2793 // Target pressure for the tissue is the Buhlmann limit. We use the Buhlmann
+ − 2794 // coefficients for N2 also for He because it is easier to calculate and the
+ − 2795 // N2 coefficients are more conservative than those for He, so we are on the
+ − 2796 // safe side, too.
+ − 2797 pres_tissue_max = (P_ambient_altitude/var_N2_b + var_N2_a);
+ − 2798
+ − 2799 // Adjust target pressure in case the GF model is in use by GF-high
+ − 2800 if( char_I_deco_model != 0 )
+ − 2801 {
+ − 2802 pres_tissue_max = ((pres_tissue_max - P_ambient_altitude) * char_I_GF_High_percentage * 0.01) + P_ambient_altitude;
+ − 2803 }
+ − 2804
+ − 2805
+ − 2806 //
+ − 2807 // Desaturation time
+ − 2808 //
+ − 2809
+ − 2810 // N2: actual amount of tissue pressure above equilibrium.
+ − 2811 pres_actual = pres_tissue_N2[ci] - N2_equilibrium;
+ − 2812
+ − 2813 // N2: half-time of the current tissue
+ − 2814 var_ht = var_N2_ht;
+ − 2815
+ − 2816 // Calculate desaturation time for N2 in tissue.
+ − 2817 // Desaturated state is defined as residual tissue pressure <= 1.05 x ppN2 respired
+ − 2818
+ − 2819 pres_target = 0.05 * N2_equilibrium;
+ − 2820
+ − 2821 calc_desaturation_time_helper();
+ − 2822
+ − 2823 if( short_time > int_O_desaturation_time) int_O_desaturation_time = short_time;
+ − 2824
+ − 2825
+ − 2826 // He: actual amount of tissue pressure above equilibrium.
+ − 2827 pres_actual = pres_tissue_He[ci]; // equilibrium for He is 0 bar
+ − 2828
+ − 2829 // He: half-time of the current tissue
+ − 2830 var_ht = var_He_ht;
+ − 2831
+ − 2832 // Calculate desaturation time for He in the tissue.
+ − 2833 // Desaturated state is defined as residual tissue pressure <= 0.05 x ppN2 respired
+ − 2834
+ − 2835 pres_target = 0.05 * N2_equilibrium;
+ − 2836
+ − 2837 calc_desaturation_time_helper();
+ − 2838
+ − 2839 if( short_time > int_O_desaturation_time) int_O_desaturation_time = short_time;
+ − 2840
+ − 2841
+ − 2842 //
+ − 2843 // no-fly time
+ − 2844 //
+ − 2845
+ − 2846 // initialize search direction
+ − 2847 search_direction = 0;
+ − 2848
+ − 2849 for(;;)
+ − 2850 {
+ − 2851 // N2: actual amount of tissue pressure above equilibrium.
+ − 2852 pres_actual = pres_tissue_N2[ci] - N2_equilibrium;
+ − 2853
+ − 2854 // N2: half-time of the current tissue
+ − 2855 var_ht = var_N2_ht;
+ − 2856
+ − 2857 // Calculate no-fly time for N2 in the tissue.
+ − 2858 // Flying is permitted when the N2 pressure fits into the assigned fraction above equilibrium.
+ − 2859
+ − 2860 pres_target = (split_N2_He[ci] * 0.01) * (pres_tissue_max - N2_equilibrium);
+ − 2861
+ − 2862 if( pres_target < 0.0 ) // check if desaturation to fly target is possible
+ − 2863 {
+ − 2864 int_O_nofly_time = 288; // NO - set no-fly time to 288 * 10 min = 48 h
+ − 2865 break; // done for this compartment
+ − 2866 }
+ − 2867 else
+ − 2868 {
+ − 2869 calc_desaturation_time_helper();
+ − 2870 nofly_N2 = short_time;
+ − 2871 }
+ − 2872
+ − 2873 // He: actual amount of tissue pressure above equilibrium - equilibrium for He is 0 bar.
+ − 2874 pres_actual = pres_tissue_He[ci];
+ − 2875
+ − 2876 // He: half-time of the current tissue
+ − 2877 var_ht = var_He_ht;
+ − 2878
+ − 2879 // Calculate no-fly time for He in the tissue.
+ − 2880 // Flying is permitted when the He pressure fits into the assigned fraction.
+ − 2881
+ − 2882 pres_target = ((100 - split_N2_He[ci]) * 0.01) * (pres_tissue_max - N2_equilibrium);
+ − 2883
+ − 2884 calc_desaturation_time_helper();
+ − 2885 nofly_He = short_time;
+ − 2886
+ − 2887
+ − 2888 // Because the sum of N2 and He tissue pressures needs to fit into the Buhlmann limit for
+ − 2889 // no-fly time calculation, each gas gets assigned a fraction of the available total pressure
+ − 2890 // limit. The optimum split between the two gases can not be computed by a single formular,
+ − 2891 // because this would require the inversion of a function with two exponential terms, which is
+ − 2892 // not possible. We do not want to do a computational complex simulation here like it is done
+ − 2893 // in the deco calculation code (although we tackle the same base problem here), so we just let
+ − 2894 // the computer try out which split will balance the no-fly times induced by the N2 and the He
+ − 2895 // at best.
+ − 2896
+ − 2897 // first of all, skip any optimization in case the current compartment is not the leading one
+ − 2898 if( (nofly_N2 <= int_O_nofly_time) && (nofly_He <= int_O_nofly_time) ) break;
+ − 2899
+ − 2900 // check if the N2 requires more waiting time than the He
+ − 2901 if( nofly_N2 >= nofly_He )
+ − 2902 {
+ − 2903 // check if the search direction has changed, which means we are beyond the
+ − 2904 // optimum now, or if we are at the upper stop limit of split_N2_He
+ − 2905 if( (search_direction < 0) || (split_N2_He[ci] == 99) )
+ − 2906 {
+ − 2907 // Either the just completed iteration was more close to the optimum or the one before
+ − 2908 // was, so we take the best (i.e. shortest) time of both as the final no-fly time.
+ − 2909 int_O_nofly_time = (nofly_N2 < nofly_last) ? nofly_N2 : nofly_last;
+ − 2910 break;
+ − 2911 }
+ − 2912
+ − 2913 // store the no-fly time found in this iteration
+ − 2914 nofly_last = nofly_N2;
+ − 2915
+ − 2916 // increase the N2 fraction of the split and set search direction towards more N2
+ − 2917 split_N2_He[ci] += 1;
+ − 2918 search_direction = +1;
+ − 2919 }
+ − 2920 else
+ − 2921 {
+ − 2922 // check if the search direction has changed, which means we are beyond the
+ − 2923 // optimum now, or if we are at the lower stop limit of split_N2_He
+ − 2924 if( (search_direction > 0) || (split_N2_He[ci] == 1) )
+ − 2925 {
+ − 2926 // Either the just completed iteration was more close to the optimum or the one before
+ − 2927 // was, so we take the best (i.e. shortest) time of both as the final no-fly time.
+ − 2928 int_O_nofly_time = (nofly_He < nofly_last) ? nofly_He : nofly_last;
+ − 2929 break;
+ − 2930 }
+ − 2931
+ − 2932 // store the no-fly time found in this iteration
+ − 2933 nofly_last = nofly_He;
+ − 2934
+ − 2935 // decrease the N2 fraction of the split and set search direction towards less N2
+ − 2936 split_N2_He[ci] -= 1;
+ − 2937 search_direction = -1;
+ − 2938 }
+ − 2939
+ − 2940 } // for(;;)
+ − 2941
+ − 2942 } // for(compartments)
+ − 2943
+ − 2944
+ − 2945 // Rescale int_O_desaturation_time and int_O_nofly_time to full minutes for display purpose
+ − 2946 int_O_desaturation_time *= 10;
+ − 2947 int_O_nofly_time *= 10;
+ − 2948
+ − 2949 // Limit int_O_desaturation_time and int_O_nofly_time to 5999 = 99 hours + 59 minutes
+ − 2950 // because of display space constraints and rounding done above.
+ − 2951 if( int_O_desaturation_time > 5999 ) int_O_desaturation_time = 5999;
+ − 2952 if( int_O_nofly_time > 5999 ) int_O_nofly_time = 5999;
+ − 2953
+ − 2954
+ − 2955 // Clear the microbubbles warning when the current gradient factor is < GF_warning_threshold.
+ − 2956 // As the locked warning will stay set, this will cause the warning be be displayed in attention
+ − 2957 // color instead of warning color.
+ − 2958 if( int_O_gradient_factor < GF_warning_threshold ) char_O_deco_warnings &= ~DECO_WARNING_MBUBBLES;
+ − 2959
+ − 2960 // clear some warnings when the desaturation time has become zero
+ − 2961 if( int_O_desaturation_time == 0 ) char_O_deco_warnings &= ~( DECO_WARNING_IBCD + DECO_WARNING_IBCD_lock
+ − 2962 + DECO_WARNING_MBUBBLES + DECO_WARNING_MBUBBLES_lock
+ − 2963 + DECO_WARNING_OUTSIDE + DECO_WARNING_OUTSIDE_lock );
+ − 2964
+ − 2965 }
+ − 2966
+ − 2967 //////////////////////////////////////////////////////////////////////////////
+ − 2968 // calc_wo_deco_step_1_min
+ − 2969 //
+ − 2970 // optimized in v.101 (...saturation_multiplier)
+ − 2971 // desaturation slowed down to 70,42%
+ − 2972 //
+ − 2973 // Input: int_I_pres_surface [mbar]
+ − 2974 //
+ − 2975 static void calc_wo_deco_step_1_min(void)
+ − 2976 {
+ − 2977 assert( 800 < int_I_pres_surface && int_I_pres_surface < 1100 );
+ − 2978 assert( 100 <= char_I_saturation_multiplier && char_I_saturation_multiplier < 200 );
+ − 2979 assert( 0 < char_I_desaturation_multiplier && char_I_desaturation_multiplier <= 100 );
+ − 2980
+ − 2981 // setup input data for deco routines
+ − 2982 pres_respiration = pres_surface = int_I_pres_surface * 0.001;
+ − 2983
+ − 2984 N2_ratio = 0.7902; // according to Buhlmann
+ − 2985 N2_equilibrium = N2_ratio * (pres_surface - ppWater); // used for N2 tissue graphics scaling
+ − 2986 ppN2 = N2_ratio * (pres_respiration - ppWater);
+ − 2987 ppHe = 0.0;
+ − 2988
+ − 2989 float_desaturation_multiplier = char_I_desaturation_multiplier * 0.01 * SURFACE_DESAT_FACTOR;
+ − 2990 float_saturation_multiplier = char_I_saturation_multiplier * 0.01;
+ − 2991
+ − 2992
+ − 2993 // program what to do: 128 = Flag for "real" tissues, 1 = 1 minute
+ − 2994 tissue_increment = 128 + 1;
+ − 2995
+ − 2996 // update the pressure in the tissues N2/He in accordance with the new ambient pressure
+ − 2997 calc_tissue();
+ − 2998
+ − 2999 // clock down CNS by a 1 minute step
+ − 3000 CNS_fraction *= 0.992327946;
+ − 3001
+ − 3002 // compute integer copy of CNS value
+ − 3003 compute_CNS_for_display();
+ − 3004
+ − 3005 // reset deco engine start condition (probably not needed to be done here...)
+ − 3006 char_O_deco_status &= ~DECO_STATUS_MASK; // clear bits
+ − 3007 char_O_deco_status |= DECO_STATUS_INIT; // set bits
+ − 3008
+ − 3009 // reset some more data that are not applicable in surface mode
+ − 3010 char_O_nullzeit = 0;
+ − 3011 int_O_ascenttime = 0;
+ − 3012 int_O_alternate_ascenttime = 0;
+ − 3013 clear_deco_table();
+ − 3014
+ − 3015 // calculate gradient factor
+ − 3016 calc_gradient_factor();
+ − 3017 }
+ − 3018
+ − 3019 //////////////////////////////////////////////////////////////////////////////
+ − 3020 // calc_dive_interval
+ − 3021 //
+ − 3022 // Prepare tissue for delay before the next dive simulation.
+ − 3023 //
+ − 3024 // Inputs: char_I_dive_interval == delay before dive (in 1 Minute steps).
+ − 3025 // Modified: CNS_fraction, int_O_CNS_fraction
+ − 3026 // pres_tissue_N2/He[]
+ − 3027 //
+ − 3028 // Should be protected by deco_push_tissues_to_vault(),
+ − 3029 // deco_pull_tissues_from_vault()
+ − 3030 //
+ − 3031 // desaturation slowed down to 70,42%.
+ − 3032 //
+ − 3033 static void calc_dive_interval(void)
+ − 3034 {
+ − 3035 overlay unsigned char t;
+ − 3036
+ − 3037 //---- Initialize simulation parameters ----------------------------------
+ − 3038 pres_respiration = pres_surface = int_I_pres_surface * 0.001;
+ − 3039
+ − 3040 N2_ratio = 0.7902; // according to buehlmann
+ − 3041 N2_equilibrium = N2_ratio * (pres_surface - ppWater); // used for N2 tissue graphics scaling
+ − 3042 ppN2 = N2_ratio * (pres_respiration - ppWater);
+ − 3043 ppHe = 0.0;
+ − 3044
+ − 3045 float_desaturation_multiplier = char_I_desaturation_multiplier * 0.01 * SURFACE_DESAT_FACTOR;
+ − 3046 float_saturation_multiplier = char_I_saturation_multiplier * 0.01;
+ − 3047
+ − 3048 //---- Perform simulation ------------------------------------------------
+ − 3049
+ − 3050 // Calculate tissues:
+ − 3051 // Because tissue_increment is limited to 127 minutes, we have to do two passes
+ − 3052 // in case char_I_dive_interval is bigger than 127.
+ − 3053 // Ops: char_I_dive_interval must be limited to 254!
+ − 3054
+ − 3055 t = char_I_dive_interval;
+ − 3056
+ − 3057 if ( t == 255 ) t = 254;
+ − 3058
+ − 3059 if ( t > 127 ) // extra pass needed?
+ − 3060 {
+ − 3061 tissue_increment = 127 // dive interval length in minutes
+ − 3062 | 128; // Flag to update the "real" tissues
+ − 3063
+ − 3064 calc_tissue(); // update tissues
+ − 3065
+ − 3066 t -= 127; // calculate remaining dive interval length
+ − 3067 }
+ − 3068
+ − 3069 tissue_increment = t // dive interval length in minutes to do
+ − 3070 | 128; // Flag to update the "real" tissues
+ − 3071 calc_tissue(); // update tissues
+ − 3072
+ − 3073
+ − 3074 // Calculate CNS:
+ − 3075 // To speed up things and because on most invocations of this code char_I_dive_interval
+ − 3076 // is a multiple of 10 minutes, we loop the loop-counter down using two speeds.
+ − 3077
+ − 3078 t = char_I_dive_interval;
+ − 3079
+ − 3080 while ( t )
+ − 3081 {
+ − 3082 if( t > 9 )
+ − 3083 {
+ − 3084 CNS_fraction *= 0.925874712; // Half-time = 90min -> 10 min: (1/2)^(1/9)
+ − 3085 t -= 10; // fast speed looping
+ − 3086 }
+ − 3087 else
+ − 3088 {
+ − 3089 CNS_fraction *= 0.992327946; // Half-time = 90min -> 1 min: (1/2)^(1/90)
+ − 3090 t -= 1; // slow speed looping
+ − 3091 }
+ − 3092 }
+ − 3093
+ − 3094 // compute integer copy of CNS value
+ − 3095 compute_CNS_for_display();
+ − 3096 }
+ − 3097
+ − 3098 //////////////////////////////////////////////////////////////////////////////
+ − 3099 // clear_CNS_fraction
+ − 3100 //
+ − 3101 // new in v.101
+ − 3102 //
+ − 3103 void clear_CNS_fraction(void)
+ − 3104 {
+ − 3105 CNS_fraction = CNS_sim_norm_fraction = CNS_sim_alt_fraction = 0;
+ − 3106 int_O_CNS_fraction = int_O_normal_CNS_fraction = int_O_alternate_CNS_fraction = 0;
+ − 3107 }
+ − 3108
+ − 3109 //////////////////////////////////////////////////////////////////////////////
+ − 3110 // calc_CNS_fraction
+ − 3111 //
+ − 3112 // Input: char_actual_ppO2 : current ppO2 [decibars]
+ − 3113 // tissue_increment : time increment and tissue selector
+ − 3114 // CNS_fraction : current CNS% as float before period
+ − 3115 //
+ − 3116 // Output: CNS_fraction, int_O_CNS_fraction - for the real tissues
+ − 3117 // CNS_sim_norm_fraction, int_O_normal_CNS_fraction - in simulation mode, normal plan
+ − 3118 // CNS_sim_alt_fraction, int_O_alternate_CNS_fraction - in simulation mode, alternative plan
+ − 3119 //
+ − 3120 void calc_CNS_fraction(void)
+ − 3121 {
+ − 3122 overlay float time_factor = 1.0; // default is 2sec
+ − 3123 overlay float CNS_fraction_temp = 0.0;
+ − 3124
+ − 3125 assert( char_actual_ppO2 > 15 );
+ − 3126
+ − 3127 // All deco code is now invoked every second. But as the CNS update is based on
+ − 3128 // 2 seconds periods, we skip every 2nd seconds-based invocation of this function.
+ − 3129 // 128 = 128 (flag for "real" CNS) + 0 (2 seconds period)
+ − 3130 // To distribute computational load, the CNS% is calculated in "the other second"
+ − 3131 // than the tissues.
+ − 3132 if( (tissue_increment == 128) && (twosectimer) ) return;
+ − 3133
+ − 3134 // adjust time factor if minute-based stepping is commanded, mask out flag bit
+ − 3135 if( tissue_increment & 127 ) time_factor = 30.0 * (float)(tissue_increment & 127);
+ − 3136
+ − 3137
+ − 3138 //------------------------------------------------------------------------
+ − 3139 // Don't increase CNS below 0.5 bar, but keep it steady.
+ − 3140 if (char_actual_ppO2 < 50)
+ − 3141 ; // no changes
+ − 3142 //------------------------------------------------------------------------
+ − 3143 // Below (and including) 1.60 bar
+ − 3144 else if (char_actual_ppO2 < 61)
+ − 3145 CNS_fraction_temp = time_factor/(-533.07 * char_actual_ppO2 + 54000.0);
+ − 3146 else if (char_actual_ppO2 < 71)
+ − 3147 CNS_fraction_temp = time_factor/(-444.22 * char_actual_ppO2 + 48600.0);
+ − 3148 else if (char_actual_ppO2 < 81)
+ − 3149 CNS_fraction_temp = time_factor/(-355.38 * char_actual_ppO2 + 42300.0);
+ − 3150 else if (char_actual_ppO2 < 91)
+ − 3151 CNS_fraction_temp = time_factor/(-266.53 * char_actual_ppO2 + 35100.0);
+ − 3152 else if (char_actual_ppO2 < 111)
+ − 3153 CNS_fraction_temp = time_factor/(-177.69 * char_actual_ppO2 + 27000.0);
+ − 3154 else if (char_actual_ppO2 < 152)
+ − 3155 CNS_fraction_temp = time_factor/( -88.84 * char_actual_ppO2 + 17100.0);
+ − 3156 else if (char_actual_ppO2 < 167)
+ − 3157 CNS_fraction_temp = time_factor/(-222.11 * char_actual_ppO2 + 37350.0);
+ − 3158 //------------------------------------------------------------------------
+ − 3159 // Arieli et all.(2002): Modeling pulmonary and CNS O2 toxicity:
+ − 3160 // J Appl Physiol 92: 248--256, 2002, doi:10.1152/japplphysiol.00434.2001
+ − 3161 // Formula (A1) based on value for 1.55 and c=20
+ − 3162 // example calculation: Sqrt((1.7/1.55)^20)*0.000404
+ − 3163 else if (char_actual_ppO2 < 172)
+ − 3164 CNS_fraction_temp = time_factor*0.00102;
+ − 3165 else if (char_actual_ppO2 < 177)
+ − 3166 CNS_fraction_temp = time_factor*0.00136;
+ − 3167 else if (char_actual_ppO2 < 182)
+ − 3168 CNS_fraction_temp = time_factor*0.00180;
+ − 3169 else if (char_actual_ppO2 < 187)
+ − 3170 CNS_fraction_temp = time_factor*0.00237;
+ − 3171 else if (char_actual_ppO2 < 192)
+ − 3172 CNS_fraction_temp = time_factor*0.00310;
+ − 3173 else if (char_actual_ppO2 < 198)
+ − 3174 CNS_fraction_temp = time_factor*0.00401;
+ − 3175 else if (char_actual_ppO2 < 203)
+ − 3176 CNS_fraction_temp = time_factor*0.00517;
+ − 3177 else if (char_actual_ppO2 < 233)
+ − 3178 CNS_fraction_temp = time_factor*0.0209;
+ − 3179 else
+ − 3180 CNS_fraction_temp = time_factor*0.0482; // value for 2.5 bar, used for 2.33 bar and above
+ − 3181
+ − 3182
+ − 3183 // Check from where we were called:
+ − 3184 // flag (bit 7) is set -> we were called from calc_hauptroutine()
+ − 3185 // flag (bit 7) not set -> we were called from the deco planning routines
+ − 3186 if ( tissue_increment & 128 ) CNS_fraction += CNS_fraction_temp; // real tissues
+ − 3187 else if ( char_O_deco_status & DECO_PLAN_ALTERNATE ) CNS_sim_alt_fraction += CNS_fraction_temp; // alternative plan
+ − 3188 else CNS_sim_norm_fraction += CNS_fraction_temp; // normal plan
+ − 3189
+ − 3190 }
+ − 3191
+ − 3192 //////////////////////////////////////////////////////////////////////////////
+ − 3193 // calc_CNS_planning
+ − 3194 //
+ − 3195 // Compute CNS during predicted ascent.
+ − 3196 //
+ − 3197 // Note: Needs a call to deco_push_tissues_to_vault(),
+ − 3198 // deco_pull_tissues_from_vault() to avoid trashing everything...
+ − 3199 //
+ − 3200 // Input: CNS_fraction, internal_deco_time[], internal_deco_depth[], internal_deco_gas[]
+ − 3201 // Output: CNS_fraction, int_O_normal_CNS_fraction / int_O_alternate_CNS_fraction
+ − 3202 //
+ − 3203 void calc_CNS_planning(void)
+ − 3204 {
+ − 3205 // start with CNS% we already have
+ − 3206 if( char_O_deco_status & DECO_PLAN_ALTERNATE ) CNS_sim_alt_fraction = CNS_fraction;
+ − 3207 else CNS_sim_norm_fraction = CNS_fraction;
+ − 3208
+ − 3209
+ − 3210 //---- CCR mode : do the full TTS at once ---------------------------------
+ − 3211
+ − 3212 if( ((char_O_deco_status & DECO_MODE_MASK) == DECO_MODE_CCR) )
+ − 3213 {
+ − 3214 overlay unsigned short t; // needs 16 bits here !
+ − 3215
+ − 3216 // get current ppO2 from sensors or setpoint
+ − 3217 char_actual_ppO2 = char_I_const_ppO2;
+ − 3218
+ − 3219 // calculate CNS% for the period of additional staying at bottom depth (fTTS / delayed ascent)
+ − 3220 if( char_O_deco_status & DECO_ASCENT_DELAYED)
+ − 3221 {
+ − 3222 tissue_increment = char_I_extra_time; // must be limited to 127, is limited by range of char_I_extra_time
+ − 3223 calc_CNS_fraction();
+ − 3224 }
+ − 3225
+ − 3226 // get the ascent time dependent on the current plan
+ − 3227 t = (char_O_deco_status & DECO_PLAN_ALTERNATE) ? int_O_alternate_ascenttime : int_O_ascenttime;
+ − 3228
+ − 3229 // start simulating CNS% in chunks of 127 minutes
+ − 3230 tissue_increment = 127;
+ − 3231
+ − 3232 while( t > 127 )
+ − 3233 {
+ − 3234 t -= 127; // tissue_increment is limited to 127 minutes because of flag in bit 7
+ − 3235 calc_CNS_fraction(); // calculate CNS in chunks of full 127 minutes
+ − 3236 }
+ − 3237
+ − 3238 tissue_increment = (char)t; // get the remaining minutes <= 127
+ − 3239 calc_CNS_fraction(); // calculate CNS for the remaining minutes
+ − 3240 }
+ − 3241 else //---- OC mode and pSCR without sensors: have to follow all gas switches... -----
+ − 3242 {
+ − 3243 overlay float float_actual_ppO2;
+ − 3244 overlay float abs_pres;
+ − 3245
+ − 3246 overlay unsigned char stop_depth;
+ − 3247 overlay unsigned char last_gas;
+ − 3248 overlay unsigned char i; // stop table index
+ − 3249
+ − 3250
+ − 3251 // retrieve bottom gas 0 (manual gas) or 1-5 (configured gases)
+ − 3252 last_gas = sim_gas_last_used = sim_gas_first_used;
+ − 3253
+ − 3254 // get the calc_N2/He/O2_ratios of the bottom gas
+ − 3255 gas_switch_set();
+ − 3256
+ − 3257 // calculate absolute pressure
+ − 3258 abs_pres = pres_surface + char_I_bottom_depth * METER_TO_BAR;
+ − 3259
+ − 3260 // switch on deco mode pSCR / OC
+ − 3261 if( char_O_deco_status & DECO_MODE_PSCR )
+ − 3262 {
+ − 3263 //---- pSCR calculated --------------------------------------------
+ − 3264
+ − 3265 // abs_pres is 0.0 ... in bar
+ − 3266 // calc_O2_ratio is 0.0 ... 1.0 as factor
+ − 3267 // char_I_PSCR_drop is 0 ... 15 as %
+ − 3268 // char_I_PSCR_lungratio is 5 ... 20 as %
+ − 3269 // float_actual_ppO2 is 0.0 ... in cbar (!)
+ − 3270
+ − 3271 float_actual_ppO2 = (100 * abs_pres * calc_O2_ratio)
+ − 3272 - (1.0 - calc_O2_ratio) * char_I_PSCR_drop * char_I_PSCR_lungratio;
+ − 3273 }
+ − 3274 else
+ − 3275 {
+ − 3276 //---- OC ---------------------------------------------------------
+ − 3277
+ − 3278 float_actual_ppO2 = abs_pres * calc_O2_ratio * 100; // in cbar (!)
+ − 3279 }
+ − 3280
+ − 3281 // caution: float_actual_ppO2 is in cbar here!
+ − 3282 if ( float_actual_ppO2 < 0.0 ) char_actual_ppO2 = 0;
+ − 3283 else if ( float_actual_ppO2 > 254.5 ) char_actual_ppO2 = 255;
+ − 3284 else char_actual_ppO2 = (unsigned char)(float_actual_ppO2 + 0.5);
+ − 3285
+ − 3286
+ − 3287 // simulate extended bottom time (fTTS) / delay before ascent (bailout) if configured
+ − 3288 if( char_O_deco_status & DECO_ASCENT_DELAYED )
+ − 3289 {
+ − 3290 tissue_increment = char_I_extra_time; // must be limited to 127, is limited by range of char_I_extra_time
+ − 3291 calc_CNS_fraction();
+ − 3292 }
+ − 3293
+ − 3294
+ − 3295 // For simplicity reason (non-linearity of the relation between ppO2 and CNS increments), the
+ − 3296 // whole ascent is calculated with bottom ppO2. This errs, but it does so to the safe side.
+ − 3297
+ − 3298 // calculate ascent time (integer division and generous round-up)
+ − 3299 tissue_increment = char_I_bottom_depth / char_I_ascent_speed + 1;
+ − 3300
+ − 3301 // commented out - not needed when char_I_ascent_speed is limited to a
+ − 3302 // minimum of 2.something, it is indeed limited to 5.
+ − 3303 // limit tissue_increment to 127 minutes
+ − 3304 // if( tissue_increment > 127 ) tissue_increment = 127;
+ − 3305
+ − 3306 // simulate the CNS increase
+ − 3307 calc_CNS_fraction();
+ − 3308
+ − 3309
+ − 3310 //---- Stops ---------------------------------------------------------
+ − 3311
+ − 3312 for(i=0; i<NUM_STOPS; ++i)
+ − 3313 {
+ − 3314 // get the depth of the stop
+ − 3315 stop_depth = internal_deco_depth[i];
+ − 3316
+ − 3317 // did we reach the last entry (depth = 0)? if yes, done
+ − 3318 if (stop_depth == 0) break;
+ − 3319
+ − 3320 // get the duration of the stop and the gas breathed
+ − 3321 tissue_increment = internal_deco_time[i];
+ − 3322 sim_gas_last_used = internal_deco_gas[i];
+ − 3323
+ − 3324 // do we have a gas switch?
+ − 3325 if( sim_gas_last_used != last_gas )
+ − 3326 {
+ − 3327 // yes - get new calc ratios
+ − 3328 gas_switch_set();
+ − 3329
+ − 3330 // remember new gas as last gas
+ − 3331 last_gas = sim_gas_last_used;
+ − 3332 }
+ − 3333
+ − 3334 // calculate absolute pressure at stop depth
+ − 3335 abs_pres = pres_surface + stop_depth * METER_TO_BAR;
+ − 3336
+ − 3337 // pSCR mode
+ − 3338 if( char_O_deco_status & DECO_MODE_PSCR )
+ − 3339 {
+ − 3340 // abs_pres is 0.0 ... in bar
+ − 3341 // calc_O2_ratio is 0.0 ... 1.0 as factor
+ − 3342 // char_I_PSCR_drop is 0 ... 15 as %
+ − 3343 // char_I_PSCR_lungratio is 5 ... 20 as %
+ − 3344 // float_actual_ppO2 is 0.0 ... in cbar (!)
+ − 3345
+ − 3346 float_actual_ppO2 = (100 * abs_pres * calc_O2_ratio)
+ − 3347 - (1.0 - calc_O2_ratio) * char_I_PSCR_drop * char_I_PSCR_lungratio;
+ − 3348 }
+ − 3349 else // OC mode
+ − 3350 {
+ − 3351 float_actual_ppO2 = abs_pres * calc_O2_ratio * 100; // in cbar (!)
+ − 3352 }
+ − 3353
+ − 3354 // caution: float_actual_ppO2 is in cbar here!
+ − 3355 if ( float_actual_ppO2 < 0.0 ) char_actual_ppO2 = 0;
+ − 3356 else if ( float_actual_ppO2 > 254.5 ) char_actual_ppO2 = 255;
+ − 3357 else char_actual_ppO2 = (unsigned char)(float_actual_ppO2 + 0.5);
+ − 3358
+ − 3359
+ − 3360 // ** Currently, stop times per stop entry are limited to 99 minutes in update_deco_table(),
+ − 3361 // ** so the following code block is not needed at times.
+ − 3362 //
+ − 3363 // // tissue_increment is limited to 127 when fed to deco_calc_CNS_fraction(),
+ − 3364 // // so if the stop is longer than 127 minutes (but not longer than 254 minutes!)
+ − 3365 // // we need to calculate the CNS in two chunks.
+ − 3366 // if( tissue_increment > 127)
+ − 3367 // {
+ − 3368 // tissue_increment -= 127; // subtract full 127 minutes and do the "remaining" minutes first
+ − 3369 // calc_CNS_fraction();
+ − 3370 // tissue_increment = 127; // catch up with the previously subtracted full 127 minutes
+ − 3371 // }
+ − 3372
+ − 3373 // calculate CNS% for the stop
+ − 3374 calc_CNS_fraction();
+ − 3375 }
+ − 3376 }
+ − 3377 }
+ − 3378
+ − 3379 //////////////////////////////////////////////////////////////////////////////
+ − 3380 // deco_calc_CNS_decrease_15min
+ − 3381 //
+ − 3382 // new in v.101
+ − 3383 //
+ − 3384 // calculates the half time of 90 minutes in 6 steps of 15 min
+ − 3385 // (Used in sleep mode, for low battery mode).
+ − 3386 //
+ − 3387 // Output: int_O_CNS_fraction
+ − 3388 // Uses and Updates: CNS_fraction
+ − 3389 //
+ − 3390 void deco_calc_CNS_decrease_15min(void)
+ − 3391 {
+ − 3392 RESET_C_STACK
+ − 3393
+ − 3394 // clock down CNS
+ − 3395 CNS_fraction = 0.890899 * CNS_fraction;
+ − 3396
+ − 3397 // compute integer copy of CNS value
+ − 3398 compute_CNS_for_display();
+ − 3399 }
+ − 3400
+ − 3401
+ − 3402 //////////////////////////////////////////////////////////////////////////////
+ − 3403 // gas_volumes
+ − 3404 //
+ − 3405 // calculates volumes and required tank fill pressures for each gas.
+ − 3406 //
+ − 3407 // Input: char_I_bottom_depth depth of the bottom segment
+ − 3408 // char_I_bottom_time duration of the bottom segment
+ − 3409 // char_I_extra_time extra bottom time for fTTS / delayed ascent
+ − 3410 // float_ascent_speed ascent speed, in meters/minute
+ − 3411 // sim_gas_first_used the bottom gas (1-5 for configured gases, 0 for the manual gas)
+ − 3412 // internal_deco_depth[] depth of the stops
+ − 3413 // internal_deco_time[] duration of the stops
+ − 3414 // internal_deco_gas[] gas breathed at the stops
+ − 3415 // char_I_bottom_usage gas consumption during bottom part and initial ascent, in liters/minute
+ − 3416 // char_I_deco_usage gas consumption during stops and following ascents, in liters/minute
+ − 3417 // char_I_tank_size[] size of the tanks for gas 1-5, in liters
+ − 3418 // char_I_tank_pres_fill[] fill pressure of the tanks
+ − 3419 //
+ − 3420 // Output: int_O_gas_volumes[] amount of gas needed, in liters
+ − 3421 // int_O_tank_pres_need[] in bar, + flags for fast evaluation by dive mode warnings:
+ − 3422 // 2^15: pres_need >= pres_fill
+ − 3423 // 2^14: pres_need >= press_fill * GAS_NEEDS_ATTENTION_THRESHOLD
+ − 3424 // 2^11: pres_need == 0
+ − 3425 // 2^10: pres_need invalid
+ − 3426 //
+ − 3427 void gas_volumes_helper(void)
+ − 3428 {
+ − 3429 // Calculate the gas volume needed at a given depth, time and usage (SAC rate).
+ − 3430 // We use 1.0 for the surface pressure to have stable results when used through
+ − 3431 // the deco calculator (simulation mode).
+ − 3432 volume = (float_depth * METER_TO_BAR + 1.0) * float_time * usage;
+ − 3433
+ − 3434 return;
+ − 3435 }
+ − 3436
+ − 3437 void gas_volumes(void)
+ − 3438 {
+ − 3439 overlay float volumes[NUM_GAS];
+ − 3440
+ − 3441 overlay unsigned char stop_gas;
+ − 3442 overlay unsigned char stop_gas_last;
+ − 3443 overlay unsigned char stop_time;
+ − 3444 overlay unsigned char stop_depth;
+ − 3445 overlay unsigned char stop_depth_last;
+ − 3446 overlay unsigned char i;
+ − 3447
+ − 3448
+ − 3449 //---- initialization ----------------------------------------------------
+ − 3450
+ − 3451 // null the volume accumulators
+ − 3452 for(i=0; i<NUM_GAS; ++i) volumes[i] = 0.0;
+ − 3453
+ − 3454 // quit for CCR and pSCR mode
+ − 3455 if( char_O_deco_status & DECO_MODE_LOOP ) goto done;
+ − 3456
+ − 3457
+ − 3458 //---- bottom demand -----------------------------------------------------
+ − 3459
+ − 3460 // sim_gas_first_used : gas used during bottom segment (0, 1-5)
+ − 3461 // char_I_bottom_depth: depth of the bottom segment
+ − 3462
+ − 3463 assert(0 <= sim_gas_first_used && sim_gas_first_used <= NUM_GAS);
+ − 3464
+ − 3465 // get the gas used during bottom segment
+ − 3466 stop_gas_last = stop_gas = sim_gas_first_used;
+ − 3467
+ − 3468 // set the usage (SAC rate) to bottom usage rate for bottom part and initial ascent
+ − 3469 usage = char_I_bottom_usage;
+ − 3470
+ − 3471 // volumes are only calculated for gases 1-5, but not the manually configured one
+ − 3472 if( stop_gas )
+ − 3473 {
+ − 3474 // set the bottom depth
+ − 3475 float_depth = (float)char_I_bottom_depth;
+ − 3476
+ − 3477 // calculate either bottom segment or fTTS / delayed ascent
+ − 3478 if( char_O_deco_status & DECO_ASCENT_DELAYED )
+ − 3479 {
+ − 3480 // duration of delayed ascent
+ − 3481 float_time = (float)char_I_extra_time;
+ − 3482 }
+ − 3483 else
+ − 3484 {
+ − 3485 // duration of bottom segment
+ − 3486 float_time = (float)char_I_bottom_time;
+ − 3487 }
+ − 3488
+ − 3489 // calculate gas demand
+ − 3490 gas_volumes_helper();
+ − 3491
+ − 3492 // take result
+ − 3493 volumes[stop_gas-1] = volume;
+ − 3494 }
+ − 3495
+ − 3496
+ − 3497 // initialize stop index with first stop
+ − 3498 i = 0;
+ − 3499
+ − 3500
+ − 3501 //---- initial ascent demand ---------------------------------------------
+ − 3502
+ − 3503 // stop_gas : gas from bottom segment
+ − 3504 // char_I_bottom_depth : depth of the bottom segment
+ − 3505 // internal_deco_depth[i=0]: depth of the first stop, may be 0 if no stop exists
+ − 3506
+ − 3507 // get the data of the first stop
+ − 3508 stop_depth = internal_deco_depth[i];
+ − 3509 stop_time = internal_deco_time[i];
+ − 3510
+ − 3511 // volumes are only calculated for gases 1-5, but not the manually configured one
+ − 3512 if( stop_gas )
+ − 3513 {
+ − 3514 // compute distance between bottom and first stop
+ − 3515 float_depth = (float)char_I_bottom_depth - (float)stop_depth;
+ − 3516
+ − 3517 // initial ascent exists only if ascent distance is > 0
+ − 3518 if( float_depth > 0.0 )
+ − 3519 {
+ − 3520 // compute ascent time
+ − 3521 float_time = float_depth / float_ascent_speed;
+ − 3522
+ − 3523 // compute average depth between bottom and first stop
+ − 3524 float_depth = (float)char_I_bottom_depth - float_depth * 0.5;
+ − 3525
+ − 3526 // calculate gas demand
+ − 3527 gas_volumes_helper();
+ − 3528
+ − 3529 // add result
+ − 3530 volumes[stop_gas-1] += volume;
+ − 3531 }
+ − 3532 }
+ − 3533
+ − 3534 // switch the usage (SAC rate) to deco usage rate
+ − 3535 // for stops, intermediate and final ascent
+ − 3536 usage = char_I_deco_usage;
+ − 3537
+ − 3538 // is there a (first) stop? if yes, goto stops processing
+ − 3539 if( stop_depth ) goto stops;
+ − 3540
+ − 3541 // add demand of a 3 minutes safety stop at 5 meters, at least for contingency...
+ − 3542 float_time = 3.0;
+ − 3543 float_depth = 5.0;
+ − 3544
+ − 3545 // calculate gas demand
+ − 3546 gas_volumes_helper();
+ − 3547
+ − 3548 // add result
+ − 3549 volumes[stop_gas-1] += volume;
+ − 3550
+ − 3551 // proceed to volume conversion and pressure calculations
+ − 3552 goto done;
+ − 3553
+ − 3554
+ − 3555 //---- intermediate ascent demand ---------------------------------------
+ − 3556 inter_ascents:
+ − 3557
+ − 3558 // store last stop depth and gas
+ − 3559 stop_depth_last = stop_depth;
+ − 3560 stop_gas_last = stop_gas;
+ − 3561
+ − 3562 // check if we are at the end of the stops table
+ − 3563 if( i < NUM_STOPS-1 )
+ − 3564 {
+ − 3565 // there are more entries - get the next stop data
+ − 3566 i++;
+ − 3567
+ − 3568 // get the next stop depth
+ − 3569 stop_depth = internal_deco_depth[i];
+ − 3570
+ − 3571 // check if there is indeed another stop,
+ − 3572 // if not (depth = 0) treat as end of table
+ − 3573 if( stop_depth == 0 ) goto end_of_table;
+ − 3574
+ − 3575 // get the next stop duration
+ − 3576 stop_time = internal_deco_time[i];
+ − 3577 }
+ − 3578 else
+ − 3579 {
+ − 3580 end_of_table:
+ − 3581
+ − 3582 // End of the stops table reached or no more stops: Split the remaining
+ − 3583 // ascent into an intermediate ascent and a final ascent by creating a
+ − 3584 // dummy stop at the usual last deco stop depth. Stop gas doesn't change.
+ − 3585 stop_time = 0;
+ − 3586 stop_depth = char_I_depth_last_deco;
+ − 3587 }
+ − 3588
+ − 3589 // volumes are only calculated for gases 1-5, but not the manually configured one
+ − 3590 if( stop_gas_last )
+ − 3591 {
+ − 3592 // compute distance between the two stops:
+ − 3593 // last stop will always be deeper than current stop
+ − 3594 float_depth = (float)(stop_depth_last - stop_depth);
+ − 3595
+ − 3596 // compute ascent time
+ − 3597 float_time = float_depth / float_ascent_speed;
+ − 3598
+ − 3599 // compute average depth between the two stops
+ − 3600 float_depth = (float)stop_depth_last - float_depth * 0.5;
+ − 3601
+ − 3602 // calculate gas demand
+ − 3603 gas_volumes_helper();
+ − 3604
+ − 3605 // add result
+ − 3606 volumes[stop_gas_last-1] += volume;
+ − 3607 }
+ − 3608
+ − 3609
+ − 3610 //---- next stop demand -------------------------------------------------
+ − 3611 stops:
+ − 3612
+ − 3613 // convert depth of the stop
+ − 3614 float_depth = (float)stop_depth;
+ − 3615
+ − 3616 // get the next gas
+ − 3617 stop_gas = internal_deco_gas[i];
+ − 3618
+ − 3619 // do we we have a gas change?
+ − 3620 if( stop_gas_last && (stop_gas != stop_gas_last) )
+ − 3621 {
+ − 3622 // yes - spend an additional char_I_gas_change_time on the old gas
+ − 3623 float_time = (float)char_I_gas_change_time;
+ − 3624
+ − 3625 // calculate gas demand
+ − 3626 gas_volumes_helper();
+ − 3627
+ − 3628 // add result
+ − 3629 volumes[stop_gas_last-1] += volume;
+ − 3630 }
+ − 3631
+ − 3632 // calculate and add demand on new gas for the full stop duration
+ − 3633 if( stop_gas )
+ − 3634 {
+ − 3635 // get the duration of the stop
+ − 3636 float_time = (float)stop_time;
+ − 3637
+ − 3638 // calculate gas demand
+ − 3639 gas_volumes_helper();
+ − 3640
+ − 3641 // add result to last gas
+ − 3642 volumes[stop_gas-1] += volume;
+ − 3643 }
+ − 3644
+ − 3645 // continue with the next intermediate ascent if this was not the last stop
+ − 3646 if( stop_depth > char_I_depth_last_deco ) goto inter_ascents;
+ − 3647
+ − 3648
+ − 3649 //---- final ascent demand -----------------------------------------------
+ − 3650 final_ascent:
+ − 3651
+ − 3652 // float_depth: depth of last stop
+ − 3653 // stop_gas : gas from last stop (0 or 1-5)
+ − 3654
+ − 3655 // volumes are only calculated for gases 1-5, but not the manually configured one
+ − 3656 if( stop_gas )
+ − 3657 {
+ − 3658 // set ascent time according to an ascent speed of 1 meter per minute
+ − 3659 float_time = float_depth;
+ − 3660
+ − 3661 // set half-way depth
+ − 3662 float_depth *= 0.5;
+ − 3663
+ − 3664 // calculate gas demand
+ − 3665 gas_volumes_helper();
+ − 3666
+ − 3667 // add result
+ − 3668 volumes[stop_gas-1] += volume;
+ − 3669 }
+ − 3670
+ − 3671
+ − 3672 //---- convert results for the assembler interface -----------------------------
+ − 3673 done:
+ − 3674
+ − 3675 for(i=0; i<NUM_GAS; ++i)
+ − 3676 {
+ − 3677 if( volumes[i] >= 65534.5 )
+ − 3678 {
+ − 3679 int_O_gas_volumes[i] = 65535;
+ − 3680 int_O_tank_pres_need[i] = 999 + INT_FLAG_WARNING; // 999 bar + warning flag for > pres_fill
+ − 3681 }
+ − 3682 else
+ − 3683 {
+ − 3684 overlay unsigned short tank_pres_fill = 10.0 * (unsigned short)char_I_tank_pres_fill[i];
+ − 3685
+ − 3686 // No distinct rounding done here because volumes are not accurate to the single liter anyhow
+ − 3687
+ − 3688 // convert gas volumes to integers
+ − 3689 int_O_gas_volumes[i] = (unsigned short)volumes[i];
+ − 3690
+ − 3691 // compute how much pressure in the tank will be needed [in bar] (integer-division)
+ − 3692 int_O_tank_pres_need[i] = (unsigned short)(int_O_gas_volumes[i] / char_I_tank_size[i]);
+ − 3693
+ − 3694 // limit to 999 bar because of display constraints
+ − 3695 if( int_O_tank_pres_need[i] > 999 ) int_O_tank_pres_need[i] = 999;
+ − 3696
+ − 3697 // set flags for fast evaluation by divemode check for warnings
+ − 3698 if ( int_O_tank_pres_need[i] == 0 )
+ − 3699 {
+ − 3700 // set flag for 0 bar
+ − 3701 int_O_tank_pres_need[i] |= INT_FLAG_ZERO;
+ − 3702 }
+ − 3703 else if( int_O_tank_pres_need[i] >= tank_pres_fill )
+ − 3704 {
+ − 3705 // set warning flag
+ − 3706 int_O_tank_pres_need[i] |= INT_FLAG_WARNING;
+ − 3707
+ − 3708 }
+ − 3709 else if( int_O_tank_pres_need[i] >= tank_pres_fill * GAS_NEEDS_ATTENTION_THRESHOLD )
+ − 3710 {
+ − 3711 // set pre-warning flag
+ − 3712 int_O_tank_pres_need[i] |= INT_FLAG_PREWARNING;
+ − 3713 }
+ − 3714
+ − 3715 // set invalid flag if there is an overflow in the stops table
+ − 3716 if( char_O_deco_warnings & DECO_WARNING_STOPTABLE_OVERFLOW )
+ − 3717 int_O_tank_pres_need[i] |= INT_FLAG_INVALID;
+ − 3718
+ − 3719 } // if( volumes[i] )
+ − 3720 } // for
+ − 3721 }
+ − 3722
+ − 3723 //////////////////////////////////////////////////////////////////////////////
+ − 3724
+ − 3725 void compute_CNS_for_display(void)
+ − 3726 {
+ − 3727 if ( CNS_fraction < 0.01 ) int_O_CNS_fraction = 0;
+ − 3728 else if ( CNS_fraction >= 9.985 ) int_O_CNS_fraction = 999 + INT_FLAG_WARNING;
+ − 3729 else
+ − 3730 {
+ − 3731 // convert float to integer
+ − 3732 int_O_CNS_fraction = (unsigned short)(100 * CNS_fraction + 0.5);
+ − 3733
+ − 3734 // compute warnings
+ − 3735 if ( int_O_CNS_fraction >= CNS_warning_threshold )
+ − 3736 {
+ − 3737 // reset pre-warning and set main warning flag
+ − 3738 int_O_CNS_fraction &= ~INT_FLAG_PREWARNING;
+ − 3739 int_O_CNS_fraction |= INT_FLAG_WARNING;
+ − 3740 }
+ − 3741 else if ( int_O_CNS_fraction >= CNS_prewarning_threshold )
+ − 3742 {
+ − 3743 // reset main warning but set pre-warning flag
+ − 3744 int_O_CNS_fraction &= ~INT_FLAG_WARNING;
+ − 3745 int_O_CNS_fraction |= INT_FLAG_PREWARNING;
+ − 3746 }
+ − 3747 else
+ − 3748 {
+ − 3749 // clear both warnings
+ − 3750 int_O_CNS_fraction &= ~(INT_FLAG_WARNING + INT_FLAG_PREWARNING);
+ − 3751 }
+ − 3752 }
+ − 3753 }
+ − 3754
+ − 3755 //////////////////////////////////////////////////////////////////////////////
+ − 3756
+ − 3757 void deco_push_tissues_to_vault(void)
+ − 3758 {
+ − 3759 overlay unsigned char x;
+ − 3760
+ − 3761 RESET_C_STACK
+ − 3762
+ − 3763 low_depth_norm_vault = low_depth_norm;
+ − 3764 low_depth_alt_vault = low_depth_alt;
+ − 3765 cns_vault_float = CNS_fraction;
+ − 3766 cns_vault_int = int_O_CNS_fraction;
+ − 3767 deco_warnings_vault = char_O_deco_warnings;
+ − 3768
+ − 3769 for (x=0;x<NUM_COMP;x++)
+ − 3770 {
+ − 3771 pres_tissue_N2_vault[x] = pres_tissue_N2[x];
+ − 3772 pres_tissue_He_vault[x] = pres_tissue_He[x];
+ − 3773 }
+ − 3774 }
+ − 3775
+ − 3776 void deco_pull_tissues_from_vault(void)
+ − 3777 {
+ − 3778 overlay unsigned char x;
+ − 3779
+ − 3780 RESET_C_STACK
+ − 3781
+ − 3782 low_depth_norm = low_depth_norm_vault;
+ − 3783 low_depth_alt = low_depth_alt_vault;
+ − 3784 CNS_fraction = cns_vault_float;
+ − 3785 int_O_CNS_fraction = cns_vault_int;
+ − 3786 char_O_deco_warnings = deco_warnings_vault;
+ − 3787
+ − 3788 locked_GF_step_norm = GF_delta / low_depth_norm;
+ − 3789 locked_GF_step_alt = GF_delta / low_depth_alt;
+ − 3790
+ − 3791 for (x=0; x<NUM_COMP; x++)
+ − 3792 {
+ − 3793 pres_tissue_N2[x] = pres_tissue_N2_vault[x];
+ − 3794 pres_tissue_He[x] = pres_tissue_He_vault[x];
+ − 3795 }
+ − 3796 }
+ − 3797
+ − 3798 //////////////////////////////////////////////////////////////////////////////
+ − 3799 //
+ − 3800 #ifndef CROSS_COMPILE
+ − 3801 void main() {}
+ − 3802 #endif