mk2: code_part1/OSTC_code_c_part2/p2

comparison code_part1/OSTC_code_c_part2/p2_deco.c @ 509:103051b4d9c1

NEW NDL analytic model (Erik Baker's formula)

author	JeanDo
date	Sun, 20 Nov 2011 23:14:18 +0100
parents	560764da0629
children	2a6293641d51

comparison

equal deleted inserted replaced

-:b595569e4bcc
+:103051b4d9c1
 // ** 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"
+#include "../OSTC_code_asm_part1/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)
 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 backup_sim_pres_tissue(void);
-static void restore_sim_pres_tissue(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 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.
 //---- Bank 6 parameters -----------------------------------------------------
 #pragma udata bank6=0x600
 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 7 parameters -----------------------------------------------------
 #pragma udata bank7=0x700
+// EMPTY ...
-float  sim_pres_tissue_N2[NUM_COMP];             // 32 floats = 128 bytes.
-float  sim_pres_tissue_He[NUM_COMP];             // 32 floats = 128 bytes.
-static float  sim_pres_tissue_backup_N2[NUM_COMP];
-static float  sim_pres_tissue_backup_He[NUM_COMP];
 //---- Bank 8 parameters -----------------------------------------------------
 #pragma udata bank8=0x800
 static char	  md_pi_subst[256];
 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( 0 <= ci && 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
 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 == 1)
+	if( char_I_deco_model != 0 )
 	{
 if( depth >= low_depth )
 sim_limit( GF_low );
 else
 sim_limit( GF_high - depth * locked_GF_step );
 }
 //////////////////////////////////////////////////////////////////////////////
 //
 // Input: calc_N2_ratio, calc_He_ratio : simulated gas mix.
-//        temp_deco : simulated respiration pressure + security offset (deco_distance)
+//        temp_deco : simulated respiration pressure
 //        float_deco_distance : security factor.
 //        Water-vapor pressure inside limbs (ppWater).
 //
 // Output: ppN2, ppHe.
 //
 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();
 	check_ndl();
 	    char_O_deco_status = 2; // 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.
 backup_gas_delay = sim_gas_delay;
 // 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 == 1 )
+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;
 //////////////////////////////////////////////////////////////////////////////
 // calc_nullzeit
 //
 // calculates the remaining bottom time
 //
-// unchanged in v.101
+// 2011-11-20 jDG: Changed (beta 2.06) to use Eric Baker's direct NDL formula.
+//
+// Input:  pres_respiration
+// Output: char_O_nullzeit
 //
 static void calc_nullzeit(void)
 {
-overlay unsigned char loop;
+overlay float Pin;
-update_startvalues();
+temp_deco = pres_respiration;
-	char_O_nullzeit = 0;
+sim_alveolar_presures();
-	for(loop = 1; loop <= 17; loop++)
+Pin = ppN2 + ppHe;
-	{
-		backup_sim_pres_tissue();
+char_O_nullzeit = 240;
-		sim_tissue(2);      // 10 min.
+for(ci=0; ci<NUM_COMP; ci++)
-sim_limit(GF_high);
+{
+//---- Compute composite A/B values and half times for the mix -------
-		if( sim_lead_tissue_limit > pres_surface )  // changed in v.102 , if guiding tissue can not be exposed to surface pressure immediately
+overlay float N2 = pres_tissue_N2[ci];
-{
+overlay float He = pres_tissue_He[ci];
-		    restore_sim_pres_tissue();
+overlay float p = N2 + He;
-break;
-}
+read_buhlmann_ht();
-// Validate once we know its good.
+var_N2_ht = (var_N2_ht * N2 + var_He_ht * He) / p;
-		char_O_nullzeit += 10;
-	}
+read_buhlmann_coefficients();
+var_N2_a = (var_N2_a * N2 + var_He_a * He) / p;
-	if (char_O_nullzeit < 60)
+var_N2_b = (var_N2_b * N2 + var_He_b * He) / p;
-	{
-	for(loop=1; loop <= 10; loop++)
+//---- Calc time for that tissue -------------------------------------
-		{
+// Erik Baker's formula:
-			sim_tissue(1);  // 1 min
+// M0 (M-value at surface) = var_N2_a + pres_surface/var_N2_b
-sim_limit(GF_high);
+// Pin = respirated pressure ppN2 + ppHe
+// p   = pressure inside tissue
-		if( sim_lead_tissue_limit > pres_surface)  // changed in v.102 , if guiding tissue can not be exposed to surface pressure immediately
+// 0.6931 = log(2)
-break;
+// NDL(ci) = log((Pin - p)/(Pin - M0))/log(2) * ht
-			char_O_nullzeit++;
+//
-		}
+if( Pin > p )   // Only when on-gasing
-	}
+{
-}
+overlay float M0 = (var_N2_a + pres_surface/var_N2_b);
-//////////////////////////////////////////////////////////////////////////////
+// Apply security margin when using the GF model
-// backup_sim_pres_tissue
+if( char_I_deco_model != 0 )
-//
+M0 = GF_high * (M0 - pres_surface) + pres_surface;
-void backup_sim_pres_tissue(void)
-{
+if( Pin > M0 )
-overlay unsigned char x;
+{
+overlay unsigned char indl;
-for(x=0; x<NUM_COMP; x++)
-{
+overlay float ndl = log((Pin - p)/(Pin - M0)) * var_N2_ht/0.6931;
-sim_pres_tissue_backup_N2[x] = sim_pres_tissue_N2[x];
-sim_pres_tissue_backup_He[x] = sim_pres_tissue_He[x];
+// Apply non-GF model security margins:
-}
+// Saturation factor will be applied to gas loading, accelerating
-}
+// loading, hence we should decrease NDL accordingly.
+if( char_I_deco_model == 0)
-//////////////////////////////////////////////////////////////////////////////
+ndl /= float_saturation_multiplier;
-// restore_sim_pres_tissue
-//
+if( ndl <   0.0f ) ndl = 0.0f;
-void restore_sim_pres_tissue(void)
+if( ndl > 254.5f ) ndl = 255.0f;
-{
+indl = (unsigned char)(ndl + 0.5f);
-overlay unsigned char x;
+if( indl < char_O_nullzeit )
+char_O_nullzeit = indl;
-for(x=0; x<NUM_COMP; x++)
+}
-{
+}
-sim_pres_tissue_N2[x] = sim_pres_tissue_backup_N2[x];
-sim_pres_tissue_He[x] = sim_pres_tissue_backup_He[x];
 }
 }
 //////////////////////////////////////////////////////////////////////////////
 // calc_ascenttime
 // 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 == 1 )
+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;
 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 == 1 )
+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;
 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 == 1)		// calculate relative gradient factor
+	if( char_I_deco_model != 0 )        // calculate relative gradient factor
 	{
 overlay float rgf;
 		if( low_depth < 1.5 )
 			rgf = GF_high;
 // 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)
 {
-overlay rom const float *ptr;
 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 );
-#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
 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);
-ptr = &buhlmann_ht[0];
 for(ci=0; ci<NUM_COMP; ci++)
 {
-overlay float var_N2_halftime = *ptr++;
-overlay float var_He_halftime = *ptr++;
 overlay unsigned short desat_time;    // For a particular compartiment, in min.
 overlay float temp1;
 overlay float temp2;
 overlay float temp3;
 overlay float temp4;
-assert( 4.0    <= var_N2_halftime && var_N2_halftime <= 635.0 );
+read_buhlmann_ht();
-assert( 1.5099 <= var_He_halftime && var_He_halftime <= 240.03 );
 // 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
 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_halftime * temp1 / float_desaturation_multiplier; // time necessary (in minutes ) for complete desaturation (see comment about 5 percent) , new in v.101: float_desaturation_multiplier
+temp2 = var_N2_ht * temp1 / float_desaturation_multiplier; // time necessary (in minutes ) for complete desaturation (see comment about 5 percent) , new in v.101: float_desaturation_multiplier
 }
 else
 {
 temp1 = 0.0;
 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_halftime * temp3 / float_desaturation_multiplier; // time necessary (in minutes ) for "complete" desaturation, new in v.101 float_desaturation_multiplier
+	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;

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comparison code_part1/OSTC_code_c_part2/p2_deco.c @ 509:103051b4d9c1