Mercurial > public > hwos_code
diff src/p2_deco.c @ 0:11d4fc797f74
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| author | heinrichsweikamp |
|---|---|
| date | Wed, 24 Apr 2013 19:22:45 +0200 |
| parents | |
| children | 5d4a4fb0e8a6 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/p2_deco.c Wed Apr 24 19:22:45 2013 +0200 @@ -0,0 +1,2307 @@ +// ************************************************************** +// p2_deco.c +// +// Created on: 12.05.2009 +// Author: chsw +// +// ************************************************************** + +////////////////////////////////////////////////////////////////////////////// +// OSTC - diving computer code +// Copyright (C) 2011 HeinrichsWeikamp GbR +// +// This program is free software: you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program. If not, see <http://www.gnu.org/licenses/>. +// +////////////////////////////////////////////////////////////////////////////// + +// ***************************** +// ** I N T R O D U C T I O N ** +// ***************************** +// +// OSTC +// +// code: +// p2_deco_main_c_v101.c +// part2 of the OSTC code +// code with constant O2 partial pressure routines +// under construction !! +// +// summary: +// decompression routines +// for the OSTC experimental project +// written by Christian Weikamp +// last revision __________ +// comments added _________ +// +// additional files: +// p2_tables_v100.romdata (other files) +// 18f4685_ostc_v100.lkr (linker script) +// +// history: +// 01/03/08 v100: first release candidate +// 03/13/08 v101: start of programming ppO2 code +// 03/13/25 v101a: backup of interrim version with ppO2 calculation +// 03/13/25 v101: open circuit gas change during deco +// 03/13/25 v101: CNS_fraction calculation +// 03/13/26 v101: optimization of tissue calc routines +// 07/xx/08 v102a: debug of bottom time routine +// 09/xx/08 v102d: Gradient Factor Model implemenation +// 10/10/08 v104: renamed to build v103 for v118 stable +// 10/14/08 v104: integration of char_I_depth_last_deco for Gradient Model +// 03/31/09 v107: integration of FONT Incon24 +// 05/23/10 v109: 5 gas changes & 1 min timer +// 07/13/10 v110: cns vault added +// 12/25/10 v110: split in three files (deco.c, main.c, definitions.h) +// 2011/01/20: [jDG] Create a common file included in ASM and C code. +// 2011/01/24: [jDG] Make ascenttime an short. No more overflow! +// 2011/01/25: [jDG] Fusion deco array for both models. +// 2011/01/25: [jDG] Use CF(54) to reverse deco order. +// 2011/02/11: [jDG] Reworked gradient-factor implementation. +// 2011/02/15: [jDG] Fixed inconsistencies introduced by gas switch delays. +// 2011/03/21: [jDG] Added gas consumption (CF56 & CF57) evaluation for OCR mode. +// 2011/04/15: [jDG] Store low_depth in 32bits (w/o rounding), for a better stability. +// 2011/04/25: [jDG] Added 1mn mode for CNS calculation, to allow it for decoplanning. +// 2011/04/27: [jDG] Fixed char_O_gradient_factor calculation when model uses gradient-factor. +// 2011/05/02: [jDG] Added "Future TTS" function (CF58). +// 2011/05/17: [jDG] Various cleanups. +// 2011/08/08: [jDG] Computes CNS during deco planning ascent. +// 2011/11/24: [jDG] Slightly faster and better NDL computation. +// 2011/12/17: [mH] Remove of the useless debug stuff +// 2012/02/24: [jDG] Remove missed stop bug. +// 2012/02/25: [jDG] Looking for a more stable LOW grad factor reference. +// 2012/09/10: [mH] Fill char_O_deco_time_for_log for logbook write +// 2012/10/05: [jDG] Better deco_gas_volumes accuracy (average depth, switch between stop). +// 2013/03/05: [jDG] Should vault low_depth too. +// 2013/03/05: [jDG] Wrobell remark: ascent_to_first_stop works better with finer steps (2sec). +// +// TODO: +// +// Literature: +// Bühlmann, Albert: Tauchmedizin; 4. Auflage [2002]; +// 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 +// Morrison, Stuart; 2000; DIY DECOMPRESSION; http://www.lizardland.co.uk/DIYDeco.html +// Balthasar, Steffen; Dekompressionstheorie I: Neo Haldane Modelle; http://www.txfreak.de/dekompressionstheorie_1.pdf +// Baker, Erik C.; Clearing Up The Confusion About "Deep Stops" +// Baker, Erik C.; Understanding M-values; http://www.txfreak.de/understanding_m-values.pdf +// +// + +// ********************* +// ** I N C L U D E S ** +// ********************* +#include <math.h> + +// *********************************************** +// ** V A R I A B L E S D E F I N I T I O N S ** +// *********************************************** + +#include "p2_definitions.h" +#define TEST_MAIN +#include "shared_definitions.h" + +// Water vapour partial pressure in the lumb. +#define ppWater 0.0627 +#define METER_TO_BAR 0.09985 +#define BAR_TO_METER 10.0150 // (1.0/METER_TO_BAR) + +// Surface security factor +#define SURFACE_DESAT_FACTOR 0.7042 + +// ************************* +// ** P R O T O T Y P E S ** +// ************************* + +static void calc_hauptroutine(void); +static void calc_nullzeit(void); + +static void calc_tissue(PARAMETER unsigned char period); +static void calc_limit(void); + +static void clear_tissue(void); +static void calc_ascenttime(void); +static void update_startvalues(void); +static void clear_deco_table(void); +static unsigned char update_deco_table(void); + +static void sim_tissue(PARAMETER unsigned char period); +static void sim_limit(PARAMETER float GF_current); +static void sim_extra_time(void); +static void calc_dive_interval(void); + +static void calc_gradient_factor(void); +static void calc_wo_deco_step_1_min(void); + +static void calc_hauptroutine_data_input(void); +static void calc_hauptroutine_update_tissues(void); +static void calc_hauptroutine_calc_deco(void); +static void sim_ascent_to_first_stop(void); + +static unsigned char gas_switch_deepest(void); +static void gas_switch_set(void); + +static unsigned char calc_nextdecodepth(void); + +//---- Bank 5 parameters ----------------------------------------------------- +#ifndef UNIX +# pragma udata bank5=0x500 +#endif + +static float GF_low; +static float GF_high; +static float GF_delta; +static float locked_GF_step; // GF_delta / low_depth + +static unsigned char temp_depth_limit; +static unsigned char low_depth; // Depth of deepest stop + +// Simulation context: used to predict ascent. +static unsigned char sim_lead_tissue_no; // Leading compatiment number. +static float sim_lead_tissue_limit; // Buhlmann tolerated pressure. + +// Real context: what we are doing now. +static float calc_lead_tissue_limit; // + +static unsigned char internal_deco_time[NUM_STOPS]; +static unsigned char internal_deco_depth[NUM_STOPS]; + +static float cns_vault; +static float low_depth_vault; +static float pres_tissue_N2_vault[NUM_COMP]; +static float pres_tissue_He_vault[NUM_COMP]; + +//---- Bank 6 parameters ----------------------------------------------------- +#ifndef UNIX +# pragma udata bank6=0x600 +#endif + +static unsigned char ci; +static float pres_respiration; +static float pres_surface; +static float temp_deco; +static float ppN2; +static float ppHe; +static float temp_tissue; +static float N2_ratio; // Breathed gas nitrogen ratio. +static float He_ratio; // Breathed gas helium ratio. +static float var_N2_a; // Bühlmann a, for current N2 tissue. +static float var_N2_b; // Bühlmann b, for current N2 tissue. +static float var_He_a; // Bühlmann a, for current He tissue. +static float var_He_b; // Bühlmann b, for current He tissue. +static float var_N2_e; // Exposition, for current N2 tissue. +static float var_He_e; // Exposition, for current He tissue. +static float var_N2_ht; // Half-time for current N2 tissue. +static float var_He_ht; // Half-time for current N2 tissue. + +static float pres_diluent; // new in v.101 +static float const_ppO2; // new in v.101 + +static unsigned char sim_gas_last_depth; // Depth of last used gas, to detected a gas switch. +static unsigned char sim_gas_last_used; // Number of last used gas, to detected a gas switch. +static unsigned short sim_dive_mins; // Simulated dive time. +static float calc_N2_ratio; // Simulated (switched) nitrogen ratio. +static float calc_He_ratio; // Simulated (switched) helium ratio. +static float CNS_fraction; // new in v.101 +static float float_saturation_multiplier; // new in v.101 +static float float_desaturation_multiplier; // new in v.101 +static float float_deco_distance; // new in v.101 +//static char flag_in_divemode; // new in v.108 + +static unsigned char deco_gas_change[NUM_GAS]; // new in v.109 + +//---- Bank 7 parameters ----------------------------------------------------- +#ifndef UNIX +# pragma udata bank7=0x700 +#endif + +float pres_tissue_N2[NUM_COMP]; +float pres_tissue_He[NUM_COMP]; +float sim_pres_tissue_N2[NUM_COMP]; // 16 floats = 64 bytes. +float sim_pres_tissue_He[NUM_COMP]; // 16 floats = 64 bytes. + +//---- Bank 8 parameters ----------------------------------------------------- +#ifndef UNIX +# pragma udata overlay bank8=0x800 + static char md_pi_subst[256]; +# define C_STACK md_pi_subst // Overlay C-code data stack here, too. +#endif + +// Back to bank6 for further tmp data +#ifndef UNIX +# pragma udata bank6 +#endif + +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +///////////////////////////// THE LOOKUP TABLES ////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +// +// End of PROM code is 17F00, So push tables on PROM top... +// +#ifndef UNIX +# pragma romdata buhlmann_tables = 0x1DD00 // Needs to be in UPPER bank. +#endif + +#include "p2_tables.romdata" // new table for deco_main_v.101 (var_N2_a modified) + +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +////////////////////////////// THE SUBROUTINES /////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +// +// all new in v.102 +// moved from 0x0D000 to 0x0C000 in v.108 +#ifndef UNIX +# pragma code p2_deco = 0x0C000 +#endif + +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +/////////////////////// U T I L I T I E S ///////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// + +////////////////////////////////////////////////////////////////////////////// +// Bump to blue-screen when an assert is wrong +#ifdef __DEBUG +void assert_failed(PARAMETER short int line) +{ +} +#endif + +////////////////////////////////////////////////////////////////////////////// +// When calling C code from ASM context, the data stack pointer and +// frames should be reset. Bank8 is used by stack + +#ifdef CROSS_COMPILE +# define RESET_C_STACK +#else +# ifdef __DEBUG +# define RESET_C_STACK fillDataStack(); + void fillDataStack(void) + { + _asm + LFSR 1,C_STACK + MOVLW 0xCC + loop: MOVWF POSTINC1,0 + TSTFSZ FSR1L,0 + BRA loop + + LFSR 1,C_STACK + LFSR 2,C_STACK + _endasm + } +# else +# define RESET_C_STACK \ + _asm \ + LFSR 1, C_STACK \ + LFSR 2, C_STACK \ + _endasm +# endif +#endif + +////////////////////////////////////////////////////////////////////////////// +// Fast subroutine to read timer 5. +// Note: result is in 1/32 of msecs (30,51757813µs/bit to be precise) +static unsigned short tmr5(void) +{ +#ifndef CROSS_COMPILE + _asm + movff 0xf7c,PRODL // TMR5L + movff 0xf7d,PRODH // TMR5H + _endasm // result in PRODH:PRODL. +#else + return 0; +#endif +} + + +////////////////////////////////////////////////////////////////////////////// +// read buhlmann tables A and B for compatriment ci +// +static void read_buhlmann_coefficients(void) +{ +#ifndef CROSS_COMPILE + // Note: we don't use far rom pointer, because the + // 24 bits is too complex, hence we have to set + // the UPPER page ourself... + // --> Set zero if tables are moved to lower pages ! + _asm + movlw 1 + movwf TBLPTRU,0 + _endasm +#endif + + assert( ci < NUM_COMP ); + + // Use an interleaved array (AoS) to access coefficients with a + // single addressing. + { + overlay rom const float* ptr = &buhlmann_ab[4*ci]; + var_N2_a = *ptr++; + var_N2_b = *ptr++; + var_He_a = *ptr++; + var_He_b = *ptr++; + } +} + +////////////////////////////////////////////////////////////////////////////// +// read buhlmann tables for compatriment ci +// If period == 0 : 2sec interval +// 1 : 1 min interval +// 2 : 10 min interval. +static void read_buhlmann_times(PARAMETER char period) +{ +#ifndef CROSS_COMPILE + // Note: we don't use far rom pointer, because the + // 24 bits is to complex, hence we have to set + // the UPPER page ourself... + // --> Set zero if tables are moved to lower pages ! + _asm + movlw 1 + movwf TBLPTRU,0 + _endasm +#endif + + assert( ci < NUM_COMP ); + + // Integration intervals. + switch(period) + { + case 0: //---- 2 sec ----------------------------------------------------- + { + overlay rom const float* ptr = &e2secs[2*ci]; + var_N2_e = *ptr++; + var_He_e = *ptr++; + } + break; + + case 1: //---- 1 min ----------------------------------------------------- + { + overlay rom const float* ptr = &e1min[2*ci]; + var_N2_e = *ptr++; + var_He_e = *ptr++; + } + break; + + case 2: //---- 10 min ---------------------------------------------------- + { + overlay rom const float* ptr = &e10min[2*ci]; + var_N2_e = *ptr++; + var_He_e = *ptr++; + } + break; + + default: + assert(0); // Never go there... + } +} + +////////////////////////////////////////////////////////////////////////////// +// read buhlmann tables for compatriment ci +// +static void read_buhlmann_ht(void) +{ + +#ifndef CROSS_COMPILE + // Note: we don't use far rom pointer, because the + // 24 bits is to complex, hence we have to set + // the UPPER page ourself... + // --> Set zero if tables are moved to lower pages ! + _asm + movlw 1 + movwf TBLPTRU,0 + _endasm +#endif + + assert( ci < NUM_COMP ); + { + overlay rom const float* ptr = &buhlmann_ht[2*ci]; + var_N2_ht = *ptr++; + var_He_ht = *ptr++; + } + + assert( 4.0 <= var_N2_ht && var_N2_ht <= 635.0 ); + assert( 1.5099 <= var_He_ht && var_He_ht <= 240.03 ); +} + +////////////////////////////////////////////////////////////////////////////// +// calc_nextdecodepth +// +// new in v.102 +// +// INPUT, changing during dive: +// temp_deco +// low_depth +// +// INPUT, fixed during dive: +// pres_surface +// GF_delta +// GF_high +// GF_low +// char_I_depth_last_deco +// float_deco_distance +// +// RETURN TRUE iff a stop is needed. +// +// OUTPUT +// locked_GF_step +// temp_depth_limt +// low_depth +// +static unsigned char calc_nextdecodepth(void) +{ + //--- Max ascent speed --------------------------------------------------- + // Recompute leading gas limit, at current depth: + overlay float depth = (temp_deco - pres_surface) * BAR_TO_METER; + + // At most, ascent 1 minute, at 10m/min == 10.0 m. + overlay float min_depth = (depth > 10.0) ? (depth - 10.0) : 0.0; + + // Do we need to stop at current depth ? + overlay unsigned char need_stop = 0; + + assert( depth >= -0.2 ); // Allow for 200mbar of weather change. + + //---- ZH-L16 + GRADIENT FACTOR model ------------------------------------ + if( char_I_deco_model != 0 ) + { + overlay unsigned char first_stop = 0; + overlay float p; + + sim_limit( GF_low ); + p = sim_lead_tissue_limit - pres_surface; + if( p <= 0.0f ) + goto no_deco_stop; // We can surface directly... + + p *= BAR_TO_METER; + if( p < min_depth ) + goto no_deco_stop; // First stop is higher than 1' ascent. + + first_stop = 3 * (short)(0.99999 + p*0.333333); + assert( first_stop < 128 ); + + // Apply correction for the shallowest stop. + if( first_stop == 3 ) // new in v104 + first_stop = char_I_depth_last_deco; // Use last 3m..6m instead. + + // Store the deepest point needing a deco stop as the LOW reference for GF. + // NOTE: following stops will be validated using this LOW-HIGH gf scale, + // so if we want to keep coherency, we should not validate this stop + // yet, but apply the search to it, as for all the following stops afterward. + if( first_stop > low_depth ) + { + low_depth = first_stop; + locked_GF_step = GF_delta / first_stop; + } + + // We have a stop candidate. + // But maybe ascending to the next stop will diminish the constraint, + // because the GF might decrease more than the preassure gradient... + while(first_stop > 0) + { + overlay unsigned char next_stop; // Next depth (0..90m) + overlay float pres_stop; // Next pressure (bar) + + // Check max speed, or reaching surface. + if( first_stop <= min_depth ) + goto no_deco_stop; + + if( first_stop <= char_I_depth_last_deco ) // new in v104 + next_stop = 0; + else if( first_stop == 6 ) + next_stop = char_I_depth_last_deco; + else + next_stop = first_stop - 3; // Index of next (upper) stop. + + // Just a check we are indeed above LOW ref. + assert( next_stop < low_depth ); + + // Total preassure at the new stop candidate: + pres_stop = next_stop * METER_TO_BAR + + pres_surface; + + // Keep GF_low until a first stop depth is found: + sim_limit( GF_high - next_stop * locked_GF_step ); + + // Check upper limit (lowest pressure tolerated): + if( sim_lead_tissue_limit >= pres_stop ) // check if ascent to next deco stop is ok + goto deco_stop_found; + + // Else, validate that stop and loop... + first_stop = next_stop; + } + assert( first_stop == 0 ); + +no_deco_stop: + temp_depth_limit = min_depth; + goto done; + + // next stop is the last validated depth found, aka first_stop +deco_stop_found: + need_stop = 1; // Hit. + temp_depth_limit = first_stop; // Stop depth, in meter. + +done: + ; + } + else //---- ZH-L16 model ------------------------------------------------- + { + overlay float pres_gradient; + + // Original model + // optimized in v.101 + // char_I_depth_last_deco included in v.101 + + // Compute sim_lead_tissue_limit too, but just once. + sim_limit(1.0); + + pres_gradient = sim_lead_tissue_limit - pres_surface; + if (pres_gradient >= 0) + { + pres_gradient *= BAR_TO_METER/3; // Bar --> stop number; + temp_depth_limit = 3 * (short) (pres_gradient + 0.99); // --> metre : depth for deco + need_stop = 1; // Hit. + + // Implement last stop at 4m/5m/6m... + if( temp_depth_limit == 3 ) + temp_depth_limit = char_I_depth_last_deco; + } + else + temp_depth_limit = 0; + } + + //---- Check gas change -------------------------------------------------- + need_stop |= gas_switch_deepest(); // Update temp_depth_limit if there is a change, + + return need_stop; +} + +////////////////////////////////////////////////////////////////////////////// +// copy_deco_table +// +// Buffer the stops, once computed, so we can continue to display them +// while computing the next set. +// +static void copy_deco_table(void) +{ + // Copy depth of the first (deepest) stop, because when reversing + // order, it will be hard to find... + char_O_first_deco_depth = internal_deco_depth[0] & 0x7F; + char_O_first_deco_time = internal_deco_time [0]; + + { + overlay unsigned char x, y; + + for(x=0; x<NUM_STOPS; x++) + { + char_O_deco_depth[x] = internal_deco_depth[x]; + char_O_deco_time [x] = internal_deco_time [x]; + } + + //Now fill the char_O_deco_time_for_log array + //---- First: search the first non-null depth + for(x=(NUM_STOPS-1); x != 0; --x) + if( internal_deco_depth[x] != 0 ) break; + + //---- Second: copy to output table (in reverse order) + for(y=0; y<NUM_STOPS; y++, --x) + { + char_O_deco_time_for_log[y] = internal_deco_time [x]; + + // Stop only once the last transfer is done. + if( x == 0 ) break; + } + + //---- Third: fill table end with null + for(y++; y<NUM_STOPS; y++) + { + char_O_deco_time_for_log [y] = 0; + } + } +} + +////////////////////////////////////////////////////////////////////////////// +// temp_tissue_safety // +// +// outsourced in v.102 +// +// Apply safety factors for brand ZH-L16 model. +// +static void temp_tissue_safety(void) +{ + assert( 0.0 < float_desaturation_multiplier && float_desaturation_multiplier <= 1.0 ); + assert( 1.0 <= float_saturation_multiplier && float_saturation_multiplier <= 2.0 ); + + if( char_I_deco_model == 0 ) + { + if( temp_tissue < 0.0 ) + temp_tissue *= float_desaturation_multiplier; + else + temp_tissue *= float_saturation_multiplier; + } +} + +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +// ** THE JUMP-IN CODE ** +// ** for the asm code ** +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// + +////////////////////////////////////////////////////////////////////////////// +// Called every 2 seconds during diving. +// update tissues every time. +// +// Every 6 seconds (or slower when TTS > 16): +// - update deco table (char_O_deco_time/depth) with new values. +// - update ascent time, +// - set status to zero (so we can check there is new results). +// +void deco_calc_hauptroutine(void) +{ + RESET_C_STACK + calc_hauptroutine(); + int_O_desaturation_time = 65535; +} + +////////////////////////////////////////////////////////////////////////////// +// Reset decompression model: +// + Set all tissues to equilibrium with Air at ambient pressure. +// + Reset last stop to 0m +// + Reset all model output. +void deco_clear_tissue(void) +{ + RESET_C_STACK + clear_tissue(); +} + +////////////////////////////////////////////////////////////////////////////// +// Called every 1 min during decoplanning. +// Update tissues for 1 min. +// +void deco_calc_tissue(void) +{ + RESET_C_STACK + calc_hauptroutine_update_tissues(); +} + +////////////////////////////////////////////////////////////////////////////// + +void deco_calc_wo_deco_step_1_min(void) +{ + RESET_C_STACK + calc_wo_deco_step_1_min(); + deco_calc_desaturation_time(); +} + +////////////////////////////////////////////////////////////////////////////// + +void deco_calc_dive_interval(void) +{ + RESET_C_STACK + calc_dive_interval(); +} + +////////////////////////////////////////////////////////////////////////////// +// Find current gas in the list (if any). +// +// Input: char_I_current_gas = 1..6 +// +// Output: sim_gas_last_depth = 0..5, temp_depth_limit. +// +static void gas_switch_find_current(void) +{ + assert( 0 < char_I_current_gas && char_I_current_gas <= (NUM_GAS+1) ); + + if( char_I_current_gas <= NUM_GAS ) // Gas1..Gas5 + { + sim_gas_last_used = char_I_current_gas; + + // Note: if current is first gas, we must find it, but not set + // last depth change to surface. + 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]; + } + else + sim_gas_last_used = 0; // Gas 6 = manual set +} + +////////////////////////////////////////////////////////////////////////////// +// Find deepest available gas. +// +// Input: temp_depth_limit, +// deco_gas_change[] +// sim_gas_depth_used, sim_dive_mins. +// +// RETURNS TRUE if a stop is needed for gas switch. +// +// Output: temp_depth_limit, sim_gas_depth_used IFF the is a switch. +// +// NOTE: might be called from bottom (when sim_gas_delay and sim_gas_depth_used +// are null), or during the ascent to make sure we are not passing a +// stop (in which case both can be already set). +// +static unsigned char gas_switch_deepest(void) +{ + overlay unsigned char switch_deco = 0, switch_last = 0; + + if (char_I_const_ppO2 == 0) + { + overlay unsigned char j; + + // Loop over all enabled gas, to find the deepest one, + // above last used gas, but below temp_depth_limit. + for(j=0; j<NUM_GAS; ++j) + { + // Gas not (yet) allowed ? Skip ! + if( temp_depth_limit > deco_gas_change[j] ) + continue; + + // Gas deeper (or equal) than the current one ? Skip ! + if( sim_gas_last_depth && deco_gas_change[j] >= sim_gas_last_depth ) + continue; + + // First, or deeper ? + if( switch_deco < deco_gas_change[j] ) + { + switch_deco = deco_gas_change[j]; + switch_last = j+1; // 1..5 + } + } + } + + // If there is a better gas available + if( switch_deco ) + { + assert( !sim_gas_last_depth || sim_gas_last_depth > switch_deco ); + + sim_gas_last_depth = switch_deco; + sim_gas_last_used = switch_last; + return 0; + } + return 0; +} + +////////////////////////////////////////////////////////////////////////////// +// Calculate gas switches +// +// +// Input: N2_ratio, He_ratio. +// sim_gas_last_used +// +// Output: calc_N2_ratio, calc_He_ratio +// +static void gas_switch_set(void) +{ + assert( sim_gas_last_used <= NUM_GAS ); + + if( sim_gas_last_used == 0 ) // Gas6 = manualy set gas. + { + calc_N2_ratio = N2_ratio; + calc_He_ratio = He_ratio; + } + else + { + calc_N2_ratio = char_I_deco_N2_ratio[sim_gas_last_used-1] * 0.01; + calc_He_ratio = char_I_deco_He_ratio[sim_gas_last_used-1] * 0.01; + } + + assert( 0.0 <= calc_N2_ratio && calc_N2_ratio <= 0.95 ); + assert( 0.0 <= calc_He_ratio && calc_He_ratio <= 0.95 ); + assert( (calc_N2_ratio + calc_He_ratio) <= 1.00 ); +} + +////////////////////////////////////////////////////////////////////////////// +// +// Input: calc_N2_ratio, calc_He_ratio : simulated gas mix. +// temp_deco : simulated respiration pressure +// float_deco_distance : security factor. +// Water-vapor pressure inside limbs (ppWater). +// +// Output: ppN2, ppHe. +// +static void sim_alveolar_presures(void) +{ + overlay float deco_diluent = temp_deco; // new in v.101 + + // Take deco offset into account, but not at surface. + // Note: this should be done on ambiant pressure, hence before + // computing the diluant partial pressure... + if( deco_diluent > pres_surface ) + deco_diluent += float_deco_distance; + + //---- CCR mode : deco gas switch ? -------------------------------------- + if( char_I_const_ppO2 != 0 ) + { + // In CCR mode, use calc_XX_ratio instead of XX_ratio. + // Note: PPO2 and ratios are known outside the lumbs, so there is no + // ppWater in the equations below: + deco_diluent -= const_ppO2; + deco_diluent /= calc_N2_ratio + calc_He_ratio; + + if (deco_diluent > temp_deco) + deco_diluent = temp_deco; + } + + if( deco_diluent > ppWater ) + { + ppN2 = calc_N2_ratio * (deco_diluent - ppWater); + ppHe = calc_He_ratio * (deco_diluent - ppWater); + } + else + { + ppN2 = 0.0; + ppHe = 0.0; + } + assert( 0.0 <= ppN2 && ppN2 < 14.0 ); + assert( 0.0 <= ppHe && ppHe < 14.0 ); +} + +////////////////////////////////////////////////////////////////////////////// +// clear_tissue +// +// optimized in v.101 (var_N2_a) +// +// preload tissues with standard pressure for the given ambient pressure. +// Note: fixed N2_ratio for standard air. +// +static void clear_tissue(void) +{ + overlay float p; + + // Kludge: the 0.0002 of 0.7902 are missing with standard air. + N2_ratio = 0.7902; + pres_respiration = int_I_pres_respiration * 0.001; + + p = N2_ratio * (pres_respiration - ppWater); + for(ci=0; ci<NUM_COMP; ci++) + { + // cycle through the 16 Bühlmann N2 tissues + pres_tissue_N2[ci] = p; + + // cycle through the 16 Bühlmann tissues for Helium + pres_tissue_He[ci] = 0.0; + } + + clear_deco_table(); +// flag_in_divemode = 0; + char_O_deco_status = 0; + char_O_nullzeit = 0; + int_O_ascenttime = 0; + char_O_gradient_factor = 0; + char_O_relative_gradient_GF = 0; + + calc_lead_tissue_limit = 0.0; + char_O_gtissue_no = 0; +} + +////////////////////////////////////////////////////////////////////////////// +// calc_hauptroutine +// +// this is the major code in dive mode calculates: +// the tissues, +// the bottom time, +// and simulates the ascend with all deco stops. +// +// The deco_state sequence is : +// 3 (at surface) +// +---> 0 : calc nullzeit +// | 2 : simulate ascent to first stop (at 10m/min, less that 16x 1min simu) +// | +-> 1 : simulate up to 16min of stops. +// | +------< not finished +// +--------< finish +// +// Added steps 6,5 for @+5 calculation: +// 6 = ascent to first stop (same as 2), except continue to 7 +// 7 = same as 1, except loop to 7. +// +static void calc_hauptroutine(void) +{ + static unsigned char backup_gas_used; + static unsigned char backup_gas_depth; + + calc_hauptroutine_data_input(); + + calc_hauptroutine_update_tissues(); + calc_gradient_factor(); + + // toggle between calculation for nullzeit (bottom time), + // deco stops + // and more deco stops (continue) + switch( char_O_deco_status ) + { + case 3: //---- At surface: start a new dive ------------------------------ + clear_deco_table(); + copy_deco_table(); + int_O_ascenttime = 0; // Reset DTR. + int_O_extra_ascenttime = 0; + char_O_nullzeit = 0; // Reset bottom time. + char_O_deco_status = 0; // Calc bottom-time/nullzeit next iteration. + + // Values that should be reset just once for the full real dive. + // This is used to record the lowest stop for the whole dive, + // Including ACCROSS all simulated ascent. + low_depth = 0; + locked_GF_step = 0.0; + + // Reset gas switch history. + backup_gas_used = sim_gas_last_used = 0; + backup_gas_depth = sim_gas_last_depth = 0; + sim_dive_mins = 0; + break; + + case 0: //---- bottom time ----------------------------------------------- + default: + gas_switch_find_current(); // Lookup for current gas & time. + gas_switch_set(); // setup calc_ratio's + + calc_nullzeit(); + if( char_O_nullzeit > 0 ) // Some NDL time left ? + { + char_O_deco_status = 0; // YES: recalc ndl next time. + clear_deco_table(); // Also clear stops ! + copy_deco_table(); + char_O_deco_last_stop = 0; // And last stop (OSTC menu anim) + } + else + char_O_deco_status = 2; // NO: calc ascent next time. + break; + + case 2: //---- Simulate ascent to first stop ----------------------------- + case 6: // @+5min variation + // Check proposed gas at begin of ascent simulation + sim_dive_mins = int_I_divemins; // Init current time. + + gas_switch_find_current(); // Lookup for current gas & time. + gas_switch_set(); // setup calc_ratio's + + backup_gas_used = sim_gas_last_used; // And save for later simu steps. + backup_gas_depth = sim_gas_last_depth; // And save for later simu steps. + + sim_ascent_to_first_stop(); + + // Calc stops next time (deco or gas switch). + char_O_deco_status = 1 | ( char_O_deco_status & 4 ); + break; + + case 1: //---- Simulate stops -------------------------------------------- + case 5: // @+5 variation. + calc_hauptroutine_calc_deco(); + + // If simulation is finished, restore the GF low reference, so that + // next ascent simulation is done from the current depth: + if( (char_O_deco_status & 3) == 0 ) + { + sim_gas_last_used = backup_gas_used; + sim_gas_last_depth = backup_gas_depth; + } + break; + } +} + +////////////////////////////////////////////////////////////////////////////// +// calc_hauptroutine_data_input +// +// Reset all C-code dive parameters from their ASM-code values. +// Detect gas change condition. +// +void calc_hauptroutine_data_input(void) +{ + overlay short int_temp; + overlay unsigned char g; + + pres_respiration = int_I_pres_respiration * 0.001; + pres_surface = int_I_pres_surface * 0.001; + N2_ratio = char_I_N2_ratio * 0.01; + He_ratio = char_I_He_ratio * 0.01; + float_deco_distance = char_I_deco_distance * 0.01; // Get offset is in mbar. + + // ____________________________________________________ + // + // _____________ G A S _ C H A N G E S ________________ + // ____________________________________________________ + + // Keep a margin of 150mbar = 1.50m + int_temp = (int_I_pres_respiration - int_I_pres_surface) + + MBAR_REACH_GASCHANGE_AUTO_CHANGE_OFF; + + // Gas are selectable if we did not pass the change depth by more than 1.50m: + for(g=0; g < NUM_GAS; ++g) + { + deco_gas_change[g] = 0; + if(char_I_deco_gas_change[g]) + if( int_temp > 100 *(short)char_I_deco_gas_change[g] ) + deco_gas_change[g] = char_I_deco_gas_change[g]; + } + + const_ppO2 = char_I_const_ppO2 * 0.01; + float_desaturation_multiplier = char_I_desaturation_multiplier * 0.01; + float_saturation_multiplier = char_I_saturation_multiplier * 0.01; + GF_low = char_I_GF_Low_percentage * 0.01; + GF_high = char_I_GF_High_percentage * 0.01; + GF_delta = GF_high - GF_low; +} + +////////////////////////////////////////////////////////////////////////////// +// +// +void calc_hauptroutine_update_tissues(void) +{ + assert( 0.00 <= N2_ratio && N2_ratio <= 1.00 ); + assert( 0.00 <= He_ratio && He_ratio <= 1.00 ); + assert( (N2_ratio + He_ratio) <= 0.95 ); + assert( 0.800 < pres_respiration && pres_respiration < 14.0 ); + + pres_diluent = pres_respiration; + if( char_I_const_ppO2 != 0 ) + { + overlay float flush_ppO2 = pres_respiration * (1.0 - N2_ratio - He_ratio); + + pres_diluent -= const_ppO2; + pres_diluent /= N2_ratio + He_ratio; + if( pres_diluent < 0.0 ) + pres_diluent = 0.0; + if( pres_diluent > pres_respiration ) + pres_diluent = pres_respiration; + + char_O_diluent = (unsigned char)(pres_diluent/pres_respiration*100.0 + 0.5); + + if( flush_ppO2 > 2.545) flush_ppO2 = 2.55; + if( flush_ppO2 < 0.0 ) flush_ppO2 = 0.0; + char_O_flush_ppO2 = (unsigned char)(flush_ppO2*100.0 + 0.5); + } + + if( pres_diluent > ppWater ) + { + overlay float EAD, END; + + ppN2 = N2_ratio * (pres_diluent - ppWater); + ppHe = He_ratio * (pres_diluent - ppWater); + + // EAD : Equivalent Air Dive. Equivalent depth for the same N2 level + // with plain air. + // ppN2 = 79% * (P_EAD - ppWater) + // EAD = (P_EAD - Psurface) * 10 + // ie: EAD = (ppN2 / 0.7902 + ppWater -Psurface) * 10 + EAD = (ppN2 / 0.7902 + ppWater - pres_surface) * BAR_TO_METER; + if( EAD < 0.0 || EAD > 245.5 ) EAD = 0.0; + char_O_EAD = (unsigned char)(EAD + 0.5); + + // END : Equivalent Narcotic Dive. + // Here we count O2 as narcotic too. Hence everything but helium (has a narcosis factor of + // 0.23 btw). Hence the formula becomes: + // END * BarPerMeter * (1.0 - 0.0) - ppWater + Psurface == Pambient - ppHe - ppWater + // ie: END = (Pambient - ppHe - Psurface) * BAR_TO_METER + // + // Source cited: + // The Physiology and Medicine of Diving by Peter Bennett and David Elliott, + // 4th edition, 1993, W.B.Saunders Company Ltd, London. + END = (pres_respiration - ppHe - pres_surface) * BAR_TO_METER; + if( END < 0.0 || END > 245.5 ) END = 0.0; + char_O_END = (unsigned char)(END + 0.5); + } + else // new in v.101 + { + ppN2 = 0.0; + ppHe = 0.0; + char_O_EAD = char_O_END = 0; + } + + if(!char_I_step_is_1min) + calc_tissue(0); + else + calc_tissue(1); + + // Calc limit for surface, ie. GF_high. + calc_limit(); + + int_O_gtissue_limit = (short)(calc_lead_tissue_limit * 1000); + int_O_gtissue_press = (short)((pres_tissue_N2[char_O_gtissue_no] + pres_tissue_He[char_O_gtissue_no]) * 1000); +} + + +////////////////////////////////////////////////////////////////////////////// +// Compute stops. +// +// Note: because this can be very long, break on 16 iterations, and set state +// to 0 when finished, or to 1 when needing to continue. +// Note: because each iteration might be very long too (~ 66 ms in 1.84beta), +// break the loop when total time > 512msec. +// +void calc_hauptroutine_calc_deco(void) +{ + overlay unsigned char loop; + + for(loop = 0; loop < 32; ++loop) + { + // Limit loops to 512ms, using timer 5: + if( tmr5() & (512*32) ) + break; + // Do not ascent while doing a gas switch ? + if( calc_nextdecodepth() ) + { + if( temp_depth_limit == 0 ) + goto Surface; + + //---- We hit a stop at temp_depth_limit --------------------- + temp_deco = temp_depth_limit * METER_TO_BAR // Convert to relative bar, + + pres_surface; // To absolute. + if( !update_deco_table() ) // Adds a one minute stops. + goto Surface; // Deco table full: abort... + } + else + { + //---- No stop ----------------------------------------------- + temp_deco -= (10*METER_TO_BAR); // Ascend 10m, no wait. + + //---- Finish computations once surface is reached ----------- + if( temp_deco <= pres_surface ) + { +Surface: + if( char_O_deco_status == 1 ) // Don't in @+5min variant. + copy_deco_table(); + + calc_ascenttime(); + char_O_deco_status = 0; // calc nullzeit next time. + char_O_deco_last_stop = 0; // Surface reached (to animate menu) + return; + } + } + //---- Then update tissue -------------------------------------------- + sim_dive_mins++; // Advance simulated time by 1 minute. + gas_switch_set(); // Apply any simulated gas change, once validated. + sim_alveolar_presures(); // Updates ppN2 and ppHe. + sim_tissue(1); // Simulate compartiments for 1 minute. + } + + // Surface not reached, need more stops... for menu animation. + char_O_deco_last_stop = temp_depth_limit; // Reached depth. +} + + +////////////////////////////////////////////////////////////////////////////// +// Simulation ascention to first deco stop. +// +// Note: because we ascent with a constant speed (10m/mn, ie. 1bar/mn), +// there is no need to break on more that 16 iterations +// (or we are already in deep shit). +// +// Input: pres_respiration +// Output: temp_deco +// +// if char_O_deco_status indicate @+5 variant, add extra time at current depth, +// before ascent. +void sim_ascent_to_first_stop(void) +{ + overlay unsigned char fast = 1; // 1min or 2sec steps. + + update_startvalues(); + clear_deco_table(); + + temp_deco = pres_respiration; // Starts from current real depth. + + // Are we doing the special @+5min variation ? + if(char_O_deco_status & 4) + sim_extra_time(); + + //---- Loop until first stop, gas switch, or surface is reached ---------- + for(;;) + { + overlay float old_deco = temp_deco; // Pamb backup (bars) + + // Try ascending 1 full minute (fast) or 2sec (!fast): + if( fast ) + temp_deco -= 10*METER_TO_BAR; // 1 min, at 10m/min. ~ 1bar. + else + temp_deco -= (10.0/30.0)*METER_TO_BAR; // 2sec at 10m/min. + + if( temp_deco < pres_surface ) // But don't go over surface. + temp_deco = pres_surface; + + // Recompute sim_lead_tissue_limit at GF_low (deepest stop), because + // one minute passed. + sim_limit(GF_low); + + // Did we reach deepest remaining stop ? + if( temp_deco < sim_lead_tissue_limit ) + { + temp_deco = old_deco; // Restore last correct depth, + + if( fast ) + { + fast = 0; // Retry with 2sec steps. + continue; + } + else + break; // Done... + } + + // Did we reach surface ? + // NOTE: we should round BEFORE checking surface is reached. + temp_depth_limit = (unsigned char)(0.5 + (temp_deco - pres_surface) * BAR_TO_METER); + if( temp_depth_limit == 0 ) + { + temp_deco = pres_surface; // Yes: finished ! + break; + } + + // Check for gas change below new depth ? + if( gas_switch_deepest() ) + { + assert( temp_depth_limit > 0); + + temp_deco = temp_depth_limit * METER_TO_BAR + pres_surface; + break; + } + + if( fast ) + sim_dive_mins++; // Advance simulated time by 1 minute. + sim_alveolar_presures(); // temp_deco --> ppN2/ppHe + sim_tissue(fast); // and update tissues for 1 min. + } +} + +////////////////////////////////////////////////////////////////////////////// +// Simulation extra time at the current depth. +// +// This routine is used for @+5min feature. +void sim_extra_time(void) +{ + overlay unsigned char extra = char_I_extra_time; + do { + sim_dive_mins++; // Advance simulated time by 1 minute. + sim_tissue(1); // and update tissues for 1 min. + } while( --extra != 0 ); +} + +////////////////////////////////////////////////////////////////////////////// +// calc_tissue +// +// optimized in v.101 +// +static void calc_tissue(PARAMETER unsigned char period) +{ + assert( 0.00 <= ppN2 && ppN2 < 11.2 ); // 80% N2 at 130m + assert( 0.00 <= ppHe && ppHe < 12.6 ); // 90% He at 130m + + for (ci=0;ci<NUM_COMP;ci++) + { + read_buhlmann_times(period); // 2 sec or 1 min period. + + // N2 + temp_tissue = (ppN2 - pres_tissue_N2[ci]) * var_N2_e; + temp_tissue_safety(); + pres_tissue_N2[ci] += temp_tissue; + + // He + temp_tissue = (ppHe - pres_tissue_He[ci]) * var_He_e; + temp_tissue_safety(); + pres_tissue_He[ci] += temp_tissue; + } +} + +////////////////////////////////////////////////////////////////////////////// +// calc_limit +// +// New in v.111 : separated from calc_tissue(), and depends on GF value. +// +static void calc_limit(void) +{ + char_O_gtissue_no = 255; + calc_lead_tissue_limit = 0.0; + + for(ci=0; ci<NUM_COMP;ci++) + { + overlay float N2 = pres_tissue_N2[ci]; + overlay float He = pres_tissue_He[ci]; + overlay float p = N2 + He; + + read_buhlmann_coefficients(); + var_N2_a = (var_N2_a * N2 + var_He_a * He) / p; + var_N2_b = (var_N2_b * N2 + var_He_b * He) / p; + + // Apply the Eric Baker's varying gradient factor correction. + // Note: the correction factor depends both on GF and b, + // Actual values are in the 1.5 .. 1.0 range (for a GF=30%), + // so that can change who is the leading gas... + // Note: Also depends of the GF. So the calcul is different for + // GF_low, current GF, or GF_high... + // *BUT* calc_tissue() is used to compute bottom time, + // hence what would happend at surface, + // hence at GF_high. + if( char_I_deco_model != 0 ) + p = ( p - var_N2_a * GF_high) * var_N2_b + / (GF_high + var_N2_b * (1.0 - GF_high)); + else + p = (p - var_N2_a) * var_N2_b; + if( p < 0.0 ) p = 0.0; + + if( p > calc_lead_tissue_limit ) + { + char_O_gtissue_no = ci; + calc_lead_tissue_limit = p; + } + } + + assert( char_O_gtissue_no < NUM_COMP ); + assert( 0.0 <= calc_lead_tissue_limit && calc_lead_tissue_limit <= 14.0); +} + +////////////////////////////////////////////////////////////////////////////// +// calc_nullzeit +// +// calculates the remaining bottom time +// +// NOTE: Erik Baker's closed formula works for Nitroxes. Trimix adds a second +// exponential term to the M-value equation, making it impossible to +// invert... So we have to make a fast-simu until we find a better way. +// +// Input: pres_respiration +// Output: char_O_nullzeit +// +static void calc_nullzeit(void) +{ + //---- Compute ppN2 and ppHe --------------------------------------------- + temp_deco = pres_respiration; + sim_alveolar_presures(); + + char_O_nullzeit = 240; + for(ci=0; ci<NUM_COMP; ci++) + { + //---- Read A/B values and loading factor for N2 and He -------------- + overlay float tN2 = pres_tissue_N2[ci]; + overlay float tHe = pres_tissue_He[ci]; + overlay float t = tN2 + tHe; + overlay unsigned char ndl; + overlay unsigned char period = 10; + + read_buhlmann_coefficients(); + read_buhlmann_times(2); // Starts with a 10min period. + + //---- Simulate for that tissue -------------------------------------- + // NOTE: No need to simulate for longuer than the already found NDL. + for(ndl=0; ndl<char_O_nullzeit;) + { + //---- Compute updated mix M-value at surface + overlay float a = (var_N2_a * tN2 + var_He_a * tHe) / t; + overlay float b = (var_N2_b * tN2 + var_He_b * tHe) / t; + overlay float M0 = (a + pres_surface/b); + + //---- Add 10min/1min to N2/He tissues + overlay float dTN2 = (ppN2 - tN2) * var_N2_e; + overlay float dTHe = (ppHe - tHe) * var_He_e; + + //---- Apply security margin when using the non-GF model + if( char_I_deco_model == 0 ) + { + dTN2 *= float_saturation_multiplier; + dTHe *= float_saturation_multiplier; + } + else // Or GF-based model + M0 = GF_high * (M0 - pres_surface) + pres_surface; + + //---- Simulate off-gasing while going to surface + // TODO ! + // dTN2 -= exp( ... ascent time ... ppN2...) + // dTHe -= exp( ... ascent time ... ppHe...) + + //---- Ok now, and still ok to surface after 1 or 10 minutes ? + if( (t <= M0) && (t + dTN2 + dTHe <= M0) ) + { + tN2 += dTN2; // YES: apply gas loadings, + tHe += dTHe; + t = tN2 + tHe; + ndl += period; // increment NDL, + continue; // and loop. + } + + //---- Should we retry with smaller steps ? + if( period == 10 ) + { + read_buhlmann_times(1); // 1min coefs. + period = 1; + continue; + } + + //---- ELSE make a linear approx for the last minute + // Usefull to have a meaningfull rounding of NDL. + // But ONLY it positive (negativ casted to unsigned is bad). + if( M0 > t ) + ndl += (unsigned char)(0.5f + (M0-t)/(dTN2+dTHe)); + break; + } + + // Keep the shortest NDL found + if( ndl < char_O_nullzeit ) + char_O_nullzeit = ndl; + } +} + +////////////////////////////////////////////////////////////////////////////// +// calc_ascenttime +// +// Summup ascent from bottom to surface, at 1 bar/min, 1min for last 3 meters, +// and all stops. +// +// Result in int_O_ascenttime, or int_O_extra_ascenttime if in @+5min variant. +static void calc_ascenttime(void) +{ + overlay unsigned char x; + overlay unsigned short sum; + + // + 0.7 to count 1 minute ascent time from 3 metre to surface + overlay float ascent = pres_respiration - pres_surface + 0.7; + if (ascent < 0.0) + ascent = 0.0; + sum = (unsigned short)(ascent + 0.99); + + for(x=0; x<NUM_STOPS && internal_deco_depth[x]; x++) + sum += (unsigned short)internal_deco_time[x]; + + if( char_O_deco_status == 1 ) + int_O_ascenttime = sum; + else + int_O_extra_ascenttime = sum; + + if(int_O_ascenttime>999) + int_O_ascenttime=999; // limit to 999' +} + +////////////////////////////////////////////////////////////////////////////// +// update_startvalues +// +// updated in v.102 +// +void update_startvalues(void) +{ + overlay unsigned char x; + + // Start ascent simulation with current tissue partial pressures. + for(x=0; x<NUM_COMP; x++) + { + sim_pres_tissue_N2[x] = pres_tissue_N2[x]; + sim_pres_tissue_He[x] = pres_tissue_He[x]; + } + + // No leading tissue (yet) for this ascent simulation. + sim_lead_tissue_limit = 0.0; + sim_lead_tissue_no = 255; +} + +////////////////////////////////////////////////////////////////////////////// +// sim_tissue +// +// optimized in v.101 +// +// Function very simular to calc_tissue, but: +// + Use a 1min or 10min period. +// + Do it on sim_pres_tissue, instead of pres_tissue. +static void sim_tissue(PARAMETER unsigned char period) +{ + assert( 0.00 <= ppN2 && ppN2 < 11.2 ); // 80% N2 at 130m + assert( 0.00 <= ppHe && ppHe < 12.6 ); // 90% He at 130m + + for(ci=0; ci<NUM_COMP; ci++) + { + read_buhlmann_times(period); // 1 or 10 minute(s) interval + + // N2 + temp_tissue = (ppN2 - sim_pres_tissue_N2[ci]) * var_N2_e; + temp_tissue_safety(); + sim_pres_tissue_N2[ci] += temp_tissue; + + // He + temp_tissue = (ppHe - sim_pres_tissue_He[ci]) * var_He_e; + temp_tissue_safety(); + sim_pres_tissue_He[ci] += temp_tissue; + } +} + +////////////////////////////////////////////////////////////////////////////// +// sim_limit() +// +// New in v.111 +// +// Function separated from sim_tissue() to allow recomputing limit on +// different depth, because it depends on current gradient factor. +// +static void sim_limit(PARAMETER float GF_current) +{ + assert( 0.0 < GF_current && GF_current <= 1.0f); + + sim_lead_tissue_limit = 0.0; + sim_lead_tissue_no = 0; // If no one is critic, keep first tissue. + + for(ci=0; ci<NUM_COMP; ci++) + { + overlay float N2 = sim_pres_tissue_N2[ci]; + overlay float He = sim_pres_tissue_He[ci]; + overlay float p = N2 + He; + + read_buhlmann_coefficients(); + var_N2_a = (var_N2_a * N2 + var_He_a * He) / p; + var_N2_b = (var_N2_b * N2 + var_He_b * He) / p; + + // Apply the Eric Baker's varying gradient factor correction. + // Note: the correction factor depends both on GF and b, + // Actual values are in the 1.5 .. 1.0 range (for a GF=30%), + // so that can change who is the leading gas... + // Note: Also depends of the GF_current... + if( char_I_deco_model != 0 ) + p = ( p - var_N2_a * GF_current) + / (GF_current / var_N2_b + 1.0 - GF_current); + else + p = (p - var_N2_a) * var_N2_b; + if( p < 0.0 ) p = 0.0; + + if( p > sim_lead_tissue_limit ) + { + sim_lead_tissue_no = ci; + sim_lead_tissue_limit = p; + } + } // for ci + + assert( sim_lead_tissue_no < NUM_COMP ); + assert( 0.0 <= sim_lead_tissue_limit && sim_lead_tissue_limit <= 14.0 ); +} + +////////////////////////////////////////////////////////////////////////////// +// clear_deco_table +// +// unchanged in v.101 +// +static void clear_deco_table(void) +{ + overlay unsigned char x; + + for(x=0; x<NUM_STOPS; ++x) + { + internal_deco_time [x] = 0; + internal_deco_depth[x] = 0; + } +} + +////////////////////////////////////////////////////////////////////////////// +// update_deco_table +// +// Add 1 min to current stop. +// +// Inputs: +// temp_depth_limit = stop's depth, in meters. +// In/Out: +// internal_deco_depth[] : depth (in metres) of each stops. +// internal_deco_time [] : time (in minutes) of each stops. +// +static unsigned char update_deco_table() +{ + overlay unsigned char x; + assert( temp_depth_limit < 128 ); // Can't be negativ (overflown). + assert( temp_depth_limit > 0 ); // No stop at surface... + + for(x=0; x<NUM_STOPS; ++x) + { + // Make sure deco-stops are recorded in order: + assert( !internal_deco_depth[x] || temp_depth_limit <= (internal_deco_depth[x]& 0x7F) ); + + if( (internal_deco_depth[x] & 0x7F) == temp_depth_limit ) + { + // Do not overflow (max 255') + if( internal_deco_time[x] < 255 ) + { + internal_deco_time[x]++; + return 1; + } + // But store extra in the next stop... + } + + if( internal_deco_depth[x] == 0 ) + { + internal_deco_depth[x] = temp_depth_limit; + + internal_deco_time[x] = 1; + return 1; + } + } + + // Can't store stops at more than 96m. + // Or stops at less that 3m too. + // Just do nothing with that... + return 0; +} + +////////////////////////////////////////////////////////////////////////////// +// calc_gradient_factor +// +// optimized in v.101 (var_N2_a) +// new code in v.102 +// +static void calc_gradient_factor(void) +{ + overlay float gf; + overlay float N2 = pres_tissue_N2[char_O_gtissue_no]; + overlay float He = pres_tissue_He[char_O_gtissue_no]; + + assert( char_O_gtissue_no < NUM_COMP ); + assert( 0.800 <= pres_respiration && pres_respiration < 14.0 ); + + // tissue > respiration (currently off-gasing) + // GF = 0% when respiration == tissue, ie. bubbles are at equilibrium. + // GF = 100% when respiration == limit. + temp_tissue = N2 + He; + if( temp_tissue <= pres_respiration ) + gf = 0.0; + else + { + overlay float limit = calc_lead_tissue_limit; + // NOTE: in GF model, calc_lead_tissue_limit include already the + // correction due to gradient factor. To compute the actual + // current GF, we need to (re-)compute the raw ambiant-pressure + // limit from the Bühlmann model. + if( char_I_deco_model != 0 ) + { + ci = char_O_gtissue_no; + read_buhlmann_coefficients(); + var_N2_a = (var_N2_a * N2 + var_He_a * He) / temp_tissue; + var_N2_b = (var_N2_b * N2 + var_He_b * He) / temp_tissue; + limit = (temp_tissue - var_N2_a) * var_N2_b; + } + + gf = (temp_tissue - pres_respiration) + / (temp_tissue - limit) + * 100.0; + if( gf > 254.5 ) gf = 255.0; + if( gf < 0.0 ) gf = 0.0; + } + char_O_gradient_factor = (unsigned char)(gf+0.5f); + + if( char_I_deco_model != 0 ) // calculate relative gradient factor + { + overlay float rgf; + + if( low_depth < 3 ) + rgf = GF_high; + else + { + overlay float temp1 = low_depth * METER_TO_BAR; + overlay float temp2 = pres_respiration - pres_surface; + + if (temp2 <= 0) + rgf = GF_high; + else if (temp2 >= temp1) + rgf = GF_low; + else + rgf = GF_low + (temp1 - temp2)/temp1*GF_delta; + } + + rgf = gf / rgf; // gf is already in percent + if( rgf < 0.0 ) rgf = 0.0; + if( rgf > 254.5 ) rgf = 255.0; + char_O_relative_gradient_GF = (unsigned char)(rgf+0.5f); + } + else + char_O_relative_gradient_GF = char_O_gradient_factor; +} + +////////////////////////////////////////////////////////////////////////////// +// deco_calc_desaturation_time +// +// FIXED N2_ratio +// unchanged in v.101 +// Inputs: int_I_pres_surface, ppWater, char_I_desaturation_multiplier +// Outputs: int_O_desaturation_time, char_O_tissue_saturation[0..31] +// +void deco_calc_desaturation_time(void) +{ + RESET_C_STACK + + assert( 800 < int_I_pres_surface && int_I_pres_surface < 1100 ); + assert( 0 < char_I_desaturation_multiplier && char_I_desaturation_multiplier <= 100 ); + + N2_ratio = 0.7902; // FIXED sum as stated in bühlmann + pres_surface = int_I_pres_surface * 0.001; + ppN2 = N2_ratio * (pres_surface - ppWater); + int_O_desaturation_time = 0; + float_desaturation_multiplier = char_I_desaturation_multiplier * (0.01 * SURFACE_DESAT_FACTOR); + + for(ci=0; ci<NUM_COMP; ci++) + { + overlay unsigned short desat_time; // For a particular compartiment, in min. + overlay float temp1; + overlay float temp2; + overlay float temp3; + overlay float temp4; + + read_buhlmann_ht(); + + // saturation_time (for flight) and N2_saturation in multiples of halftime + // version v.100: 1.1 = 10 percent distance to totally clean (totally clean is not possible, would take infinite time ) + // new in version v.101: 1.07 = 7 percent distance to totally clean (totally clean is not possible, would take infinite time ) + // changes in v.101: 1.05 = 5 percent dist to totally clean is new desaturation point for display and NoFly calculations + // N2 + temp1 = 1.05 * ppN2 - pres_tissue_N2[ci]; + temp2 = ppN2 - pres_tissue_N2[ci]; + if (temp2 >= 0.0) + temp1 = 0.0; + else + temp1 = temp1 / temp2; + + if( 0.0 < temp1 && temp1 < 1.0 ) + { + // 0.6931 is ln(2), because the math function log() calculates with a base of e not 2 as requested. + // minus because log is negative. + temp1 = log(1.0 - temp1) / -0.6931; // temp1 is the multiples of half times necessary. + temp2 = var_N2_ht * temp1 / float_desaturation_multiplier; // time necessary (in minutes ) for complete desaturation (see comment about 5 percent) + } + else + { + temp1 = 0.0; + temp2 = 0.0; + } + + // He + temp3 = 0.1 - pres_tissue_He[ci]; + if (temp3 >= 0.0) + temp3 = 0.0; + else + temp3 = - temp3 / pres_tissue_He[ci]; + + if( 0.0 < temp3 && temp3 < 1.0 ) + { + temp3 = log(1.0 - temp3) / -0.6931; // temp1 is the multiples of half times necessary. + // 0.6931 is ln(2), because the math function log() calculates with a base of e not 2 as requested. + // minus because log is negative + temp4 = var_He_ht * temp3 / float_desaturation_multiplier; // time necessary (in minutes ) for "complete" desaturation, new in v.101 float_desaturation_multiplier + } + else + { + temp3 = 0.0; + temp4 = 0.0; + } + + // saturation_time (for flight) + if (temp4 > temp2) + desat_time = (unsigned short)temp4; + else + desat_time = (unsigned short)temp2; + + if(desat_time > int_O_desaturation_time) + int_O_desaturation_time = desat_time; + + // N2 saturation in multiples of halftime for display purposes + temp2 = temp1 * 20.0; // 0 = 1/8, 120 = 0, 249 = 8 + temp2 = temp2 + 80.0; // set center + if (temp2 < 0.0) + temp2 = 0.0; + if (temp2 > 255.0) + temp2 = 255.0; + char_O_tissue_N2_saturation[ci] = (char)temp2; + + // He saturation in multiples of halftime for display purposes + temp4 = temp3 * 20.0; // 0 = 1/8, 120 = 0, 249 = 8 + temp4 = temp4 + 80.0; // set center + if (temp4 < 0.0) + temp4 = 0.0; + if (temp4 > 255.0) + temp4 = 255.0; + char_O_tissue_He_saturation[ci] = (char)temp4; + } // for +} + +////////////////////////////////////////////////////////////////////////////// +// calc_wo_deco_step_1_min +// +// FIXED N2 Ratio +// optimized in v.101 (...saturation_multiplier) +// desaturation slowed down to 70,42% +// +static void calc_wo_deco_step_1_min(void) +{ + assert( 800 < int_I_pres_surface && int_I_pres_surface < 1100 ); + assert( 800 < int_I_pres_respiration && int_I_pres_respiration < 1100 ); + assert( 100 <= char_I_saturation_multiplier && char_I_saturation_multiplier < 200 ); + assert( 0 < char_I_desaturation_multiplier && char_I_desaturation_multiplier <= 100 ); + + N2_ratio = 0.7902; // FIXED, sum lt. buehlmann + pres_respiration = pres_surface = int_I_pres_surface * 0.001; + ppN2 = N2_ratio * (pres_respiration - ppWater); + ppHe = 0.0; + float_desaturation_multiplier = char_I_desaturation_multiplier * (0.01 * SURFACE_DESAT_FACTOR); + float_saturation_multiplier = char_I_saturation_multiplier * 0.01; + + calc_tissue(1); // update the pressure in the tissues N2/He in accordance with the new ambient pressure + + clear_deco_table(); + char_O_deco_status = 3; // surface new in v.102 : stays in surface state. + char_O_nullzeit = 0; + int_O_ascenttime = 0; + int_O_extra_ascenttime = 0; + calc_gradient_factor(); +} + +////////////////////////////////////////////////////////////////////////////// +// calc_dive_interval +// +// Prepare tissue for delay before the next dive simulation. +// +// Inputs: char_I_dive_interval == delay before dive (in 10' steps). +// Outputs: pres_tissue_N2/He[], CNS_fraction +// +// Should be protected by deco_push_tissues_to_vault(), +// deco_pull_tissues_from_vault() +// +// desaturation slowed down to 70,42%. +// +static void calc_dive_interval(void) +{ + overlay unsigned char t; + overlay unsigned char backup_model; + + //---- Initialize simulation parameters ---------------------------------- + N2_ratio = 0.7902; // FIXED, sum lt. buehlmann + pres_respiration = pres_surface = int_I_pres_surface * 0.001; + ppN2 = N2_ratio * (pres_respiration - ppWater); + ppHe = 0.0; + float_desaturation_multiplier = char_I_desaturation_multiplier * (0.01 * SURFACE_DESAT_FACTOR); + float_saturation_multiplier = char_I_saturation_multiplier * 0.01; + + // Make sure SURFACE_DESAT_FACTOR is applied: + backup_model = char_I_deco_model; + char_I_deco_model = 0; + + //---- Perform simulation ------------------------------------------------ + for(t=0; t<char_I_dive_interval; ++t) + { + calc_tissue(2); // period = 10min. + CNS_fraction = 0.92587471 * CNS_fraction; // Half-time = 90min: (1/2)^(1/9) + } + assert( 0.0 <= CNS_fraction && CNS_fraction <= 2.56 ); + int_O_CNS_fraction = (unsigned int)(CNS_fraction * 100.0 + 0.5); + + //---- Restore model ----------------------------------------------------- + char_I_deco_model = backup_model; +} + +////////////////////////////////////////////////////////////////////////////// +// deco_clear_CNS_fraction +// +// new in v.101 +// +void deco_clear_CNS_fraction(void) +{ + RESET_C_STACK + + CNS_fraction = 0.0; + int_O_CNS_fraction = 0; +} + +////////////////////////////////////////////////////////////////////////////// +// deco_calc_CNS_fraction +// +// Input: char_I_actual_ppO2 : Current condition (in decibars). +// char_I_step_is_1min : use 1min or 10min steps instead of 2sec. +// CNS_fraction : velue before period. +// Output: CNS_fraction, int_O_CNS_fraction +// +void deco_calc_CNS_fraction(void) +{ + overlay float time_factor = 1.0f; + RESET_C_STACK + + assert( 0.0 <= CNS_fraction && CNS_fraction <= 2.56 ); + assert( char_I_actual_ppO2 > 15 ); + + if( char_I_step_is_1min == 1 ) + time_factor = 30.0f; + else if( char_I_step_is_1min == 2 ) + time_factor = 300.0f; + + if (char_I_actual_ppO2 < 50) + ; // no changes + else if (char_I_actual_ppO2 < 60) + CNS_fraction += time_factor/(-540.0 * char_I_actual_ppO2 + 54000.0); + else if (char_I_actual_ppO2 < 70) + CNS_fraction += time_factor/(-450.0 * char_I_actual_ppO2 + 48600.0); + else if (char_I_actual_ppO2 < 80) + CNS_fraction += time_factor/(-360.0 * char_I_actual_ppO2 + 42300.0); + else if (char_I_actual_ppO2 < 90) + CNS_fraction += time_factor/(-270.0 * char_I_actual_ppO2 + 35100.0); + else if (char_I_actual_ppO2 < 110) + CNS_fraction += time_factor/(-180.0 * char_I_actual_ppO2 + 27000.0); + else if (char_I_actual_ppO2 < 150) + CNS_fraction += time_factor/( -90.0 * char_I_actual_ppO2 + 17100.0); + else if (char_I_actual_ppO2 < 160) + CNS_fraction += time_factor/(-225.0 * char_I_actual_ppO2 + 37350.0); + else if (char_I_actual_ppO2 < 165) + CNS_fraction += time_factor*0.000755; // Arieli et all.(2002): Modeling pulmonary and CNS O2 toxicity... Formula (A1) based on value for 1.55 and c=20 + else if (char_I_actual_ppO2 < 170) + CNS_fraction += time_factor*0.00102; // example calculation: Sqrt((1.7/1.55)^20)*0.000404 + else if (char_I_actual_ppO2 < 175) + CNS_fraction += time_factor*0.00136; + else if (char_I_actual_ppO2 < 180) + CNS_fraction += time_factor*0.00180; + else if (char_I_actual_ppO2 < 185) + CNS_fraction += time_factor*0.00237; + else if (char_I_actual_ppO2 < 190) + CNS_fraction += time_factor*0.00310; + else if (char_I_actual_ppO2 < 195) + CNS_fraction += time_factor*0.00401; + else if (char_I_actual_ppO2 < 200) + CNS_fraction += time_factor*0.00517; + else if (char_I_actual_ppO2 < 230) + CNS_fraction += time_factor*0.0209; + else + CNS_fraction += time_factor*0.0482; // value for 2.5 + + if( CNS_fraction > 9.99) + CNS_fraction = 9.99; + if( CNS_fraction < 0.0 ) + CNS_fraction = 0.0; + + int_O_CNS_fraction = (unsigned int)(100.0 * CNS_fraction + 0.5); +} + +////////////////////////////////////////////////////////////////////////////// +// deco_calc_CNS_planning +// +// Compute CNS during predicted ascent. +// +// Note: Needs a call to deco_push_tissues_to_vault(), +// deco_pull_tissues_from_vault() to avoid trashing everything... +// +// Input: CNS_fraction, char_O_deco_time[], char_O_deco_depth[] +// Output: CNS_fraction, int_O_CNS_fraction +// +void deco_calc_CNS_planning(void) +{ + overlay unsigned char backup_gas_last_depth; + overlay unsigned char backup_gas_last_used; + overlay unsigned short backup_dive_mins; + overlay unsigned char backup_actual_ppO2; + + RESET_C_STACK + + // Backup state machine + backup_gas_last_depth = sim_gas_last_depth; + backup_gas_last_used = sim_gas_last_used; + backup_dive_mins = sim_dive_mins; + backup_actual_ppO2 = char_I_actual_ppO2; + + // Uses 1min CNS period: + char_I_step_is_1min = 1; + + //---- Retrieve bottom Gas used, and set variables. + sim_gas_last_used = char_I_first_gas; + sim_gas_last_depth = 0; // Surface gas marker. + gas_switch_set(); // Sets initial calc_N2/He_ratio + + //---- CCR mode : do the full TTS at once -------------------------------- + if( char_I_const_ppO2 != 0 ) + { + overlay unsigned short t; // Needs 16bits here ! + char_I_actual_ppO2 = char_I_const_ppO2; + for(t=0; t<int_O_ascenttime; ++t) + deco_calc_CNS_fraction(); + } + else //---- OC mode : have to follow all gas switches... ----------------- + { + overlay unsigned char i = 0; // Decostop loop counter + overlay float actual_ppO2; + overlay unsigned char time, t; + + //---- Ascent to surface delay + // NOTE: count as if time is spent with bottom pressure, + // AND the bottom gas + actual_ppO2 = (pres_surface + char_I_bottom_depth * METER_TO_BAR) + * (1.0 - calc_N2_ratio - calc_He_ratio); + if( actual_ppO2 < 0.0 ) actual_ppO2 = 0.0; + if( actual_ppO2 > 2.50 ) actual_ppO2 = 2.55; + char_I_actual_ppO2 = (unsigned char)(100.0 * actual_ppO2 + 0.5); + + // Ascent time (rounded up): + time = (unsigned char)(0.1 * char_I_bottom_depth + 0.5); + + for(t=0; t<time; ++t) + { + deco_calc_CNS_fraction(); + sim_dive_mins++; + } + + //---- Do all further stops ------------------------------------------ + for(i=0; i<NUM_STOPS; ++i) + { + overlay unsigned char switch_gas; + + //---- Get next stop, possibly in reverse order ------------------ + { + time = char_O_deco_time[(NUM_STOPS-1)-i]; + temp_depth_limit = char_O_deco_depth[(NUM_STOPS-1)-i]; + } + if( time == 0 ) continue; + + //---- Gas Switch ? ---------------------------------------------- + switch_gas = temp_depth_limit & 0x80; // Switch flag. + temp_depth_limit &= 0x7F; // True stop depth. + + if( switch_gas ) + { + gas_switch_deepest(); + gas_switch_set(); + } + + //---- Convert Depth and N2_ratio to ppO2 ------------------------ + actual_ppO2 = (pres_surface + temp_depth_limit * METER_TO_BAR) + * (1.0 - calc_N2_ratio - calc_He_ratio); + if( actual_ppO2 < 0.0 ) actual_ppO2 = 0.0; + if( actual_ppO2 > 2.50 ) actual_ppO2 = 2.55; + char_I_actual_ppO2 = (unsigned char)(100.0 * actual_ppO2 + 0.5); + + //---- Apply the stop + for(t=0; t<time; ++t) + { + deco_calc_CNS_fraction(); + sim_dive_mins++; + } + } + } + + //---- Back to normal mode... -------------------------------------------- + char_I_step_is_1min = 0; + sim_gas_last_depth = backup_gas_last_depth; + sim_gas_last_used = backup_gas_last_used; + sim_dive_mins = backup_dive_mins; + char_I_actual_ppO2 = backup_actual_ppO2; +} + +////////////////////////////////////////////////////////////////////////////// +// deco_calc_CNS_decrease_15min +// +// new in v.101 +// +// calculates the half time of 90 minutes in 6 steps of 15 min +// (Used in sleepmode, for low battery mode). +// +// Output: int_O_CNS_fraction +// Uses and Updates: CNS_fraction +// +void deco_calc_CNS_decrease_15min(void) +{ + RESET_C_STACK + assert( 0.0 <= CNS_fraction && CNS_fraction <= 2.56 ); + + CNS_fraction = 0.890899 * CNS_fraction; + int_O_CNS_fraction = (unsigned int)(CNS_fraction * 100.0 + 0.5); +} + +////////////////////////////////////////////////////////////////////////////// +// deco_calc_percentage +// +// new in v.101 +// +// calculates int_I_temp * char_I_temp / 100 +// output is int_I_temp +// +// Used to compute NoFly remaining time. +// +void deco_calc_percentage(void) +{ + RESET_C_STACK + + assert( 60 <= char_I_temp && char_I_temp <= 100 ); + assert( int_I_temp < 5760 ); // Less than 4 days = 96h... + + int_I_temp = (unsigned short)(((float)int_I_temp * (float)char_I_temp) * 0.01 ); + + assert( int_I_temp < 5760 ); // Less than 96h too... +} + + +////////////////////////////////////////////////////////////////////////////// +// deco_gas_volumes +// +// new in v.111 +// +// calculates volumes for each gas. +// +// Input: char_I_bottom_depth, char_I_bottom_time for planned dive. +// Gas list. +// char_I_first_gas is the bottom gas. +// decoplan (char_O_deco_depth, char_O_deco_time). +// CF#54 == TRUE if shallowest stop first. +// CF#56 == bottom liters/minutes (5 .. 50) or bar/min. +// CF#57 == deco liters/minutes (5 .. 50) or bar/min. +// Output: int_O_gas_volumes[0..4] in litters * 0.1 +// +void deco_gas_volumes(void) +{ + overlay float volumes[NUM_GAS]; + overlay float bottom_usage, deco_usage; + overlay unsigned char i, deepest_first; + overlay unsigned char gas, depth; + RESET_C_STACK + + //---- initialize with bottom consumption -------------------------------- + for(i=0; i<NUM_GAS; ++i) // Nothing yet... + volumes[i] = 0.0; + + assert(1 <= char_I_first_gas && char_I_first_gas <= NUM_GAS); + gas = char_I_first_gas - 1; + + bottom_usage = (float) char_I_bottom_usage; + if( char_I_const_ppO2 == 0 && bottom_usage > 0.0 ) + volumes[gas] + = (char_I_bottom_depth*0.1 + 1.0) // Use Psurface = 1.0 bar. + * char_I_bottom_time // in minutes. + * bottom_usage; // In liter/minutes. + + //---- Ascent usage ------------------------------------------------------ + deco_usage = (float) char_I_deco_usage; // In liter/minutes. + + depth = char_I_bottom_depth; + + for(i=0; i<NUM_STOPS; ++i) + { + overlay unsigned char newDepth, time; + + // Manage stops in reverse order (CF#54) + if( deepest_first ) + { + time = char_O_deco_time[i]; + if( time == 0 ) break; // End of table: done. + + newDepth = char_O_deco_depth[i] & 0x7F; + } + else + { + time = char_O_deco_time[31-i]; + if( time == 0 ) continue; // not yet: still search table. + + newDepth = char_O_deco_depth[31-i] & 0x7F; + } + + //---- Gas switch during this step ----------------------------------- + { + overlay unsigned char newGas = 0; + overlay unsigned char newStop = 0; // NO CHANGE yet + overlay unsigned char j; + + for(j=0; j<NUM_GAS; ++j) + { + // Skip gas without changing depth: + if( ! char_I_deco_gas_change[j] ) + continue; + // Select gas changed between [newDepth .. depth] + if( newDepth <= char_I_deco_gas_change[j] + && char_I_deco_gas_change[j] <= depth ) + { + // Keep the DEEPEST gas in that range: + // Note: that = means changing gas at BEGINNING of this stop. + if( char_I_deco_gas_change[j] >= newStop ) + { + newGas = j; + newStop = char_I_deco_gas_change[j]; + } + } + } + + if( newStop ) // Did we find something ? + { + // usage BEFORE gas switch (if any), at 10m/min : + if( deco_usage > 0.0 && depth > newStop ) + // Plus usage during ascent to the next stop, at 10m/min. + volumes[gas] += ((depth+newStop)*0.05 + 1.0) // average depth --> bar. + * (depth-newStop)*0.1 // metre --> min + * deco_usage; + + // Do gas switch: + gas = newGas; + depth = newStop; + } + } + + // usage AFTER gas switch (if any), at 10m/min : + if( depth > newDepth ) + volumes[gas] += ((depth+newDepth)*0.05 + 1.0) // average depth --> bar. + * (depth-newDepth)*0.1 // metre --> min + * deco_usage; + + // Do stop: + depth = newDepth; + + // Usage at stop: + if( deco_usage > 0.0 ) + volumes[gas] += (depth*0.1 + 1.0) // depth --> bar. + * time // in minutes. + * deco_usage; // in xxx / min @ 1bar. + else + volumes[gas] = 65535.0; + } + + // From last stop to surface + if( deco_usage > 0.0 ) + volumes[gas] += (depth*0.05 + 1.0) // avg depth --> bar. + * depth * 0.1 // time to surface, in minutes. + * deco_usage; // in xxx / min @ 1bar. + + //---- convert results for the ASM interface ----------------------------- + for(i=0; i<NUM_GAS; ++i) + if( volumes[i] > 65534.0 ) + int_O_gas_volumes[i] = 65535; + else + int_O_gas_volumes[i] = (unsigned short)(volumes[i] + 0.5); +} + +////////////////////////////////////////////////////////////////////////////// + +void deco_push_tissues_to_vault(void) +{ + overlay unsigned char x; + RESET_C_STACK + + cns_vault = CNS_fraction; + low_depth_vault = low_depth; + + for (x=0;x<NUM_COMP;x++) + { + pres_tissue_N2_vault[x] = pres_tissue_N2[x]; + pres_tissue_He_vault[x] = pres_tissue_He[x]; + } +} + +void deco_pull_tissues_from_vault(void) +{ + overlay unsigned char x; + RESET_C_STACK + + for (x=0; x<NUM_COMP; x++) + { + pres_tissue_N2[x] = pres_tissue_N2_vault[x]; + pres_tissue_He[x] = pres_tissue_He_vault[x]; + } + + // Restore both CNS variable, too. + CNS_fraction = cns_vault; + int_O_CNS_fraction = (unsigned int)(CNS_fraction * 100.0 + 0.5); + + // GF history too: + low_depth = low_depth_vault; + locked_GF_step = GF_delta / low_depth; +} + +////////////////////////////////////////////////////////////////////////////// +// +#ifndef CROSS_COMPILE +void main() {} +#endif