src/main/fuelAndIgnitionCalcs.c

   1 /* FreeEMS - the open source engine management system
   2  *
   3  * Copyright 2008-2013 Fred Cooke
   4  *
   5  * This file is part of the FreeEMS project.
   6  *
   7  * FreeEMS software is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * FreeEMS software is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with any FreeEMS software.  If not, see http://www.gnu.org/licenses/
  19  *
  20  * We ask that if you make any changes to this file you email them upstream to
  21  * us at admin(at)diyefi(dot)org or, even better, fork the code on github.com!
  22  *
  23  * Thank you for choosing FreeEMS to run your engine!
  24  */
  25
  26
  27 /** @file
  28  *
  29  * @ingroup measurementsAndCalculations
  30  *
  31  * @brief Fuel and ignition calculations.
  32  *
  33  * This file contains all of the main fuel and ignition calculations based
  34  * upon the variables that we have already determined in previous stages.
  35  */
  36
  37
  38 #define FUELANDIGNITIONCALCS_C
  39 #include "inc/freeEMS.h"
  40 #include "inc/utils.h"
  41 #include "inc/locationIDs.h"
  42 #include "inc/tableLookup.h"
  43 #include "inc/fuelAndIgnitionCalcs.h"
  44
  45
  46 /**
  47  * Final fuel and ignition calculations. Using a variety of primary algorithms
  48  * calculate a base pulsewidth and then apply various corrections to it such as
  49  * injector dead time, transient fuel correction, engine temperature enrichment
  50  * and per cylinder trims. The ignition timing and fuel injection timing are
  51  * also determined here, as are the various limiters and cuts.
  52  */
  53 void calculateFuelAndIgnition(){
  54         unsigned short airInletTemp = CoreVars->IAT; /* All except MAF use this. */
  55         /* Determine the type of air flow data */
  56         if(!(fixedConfigs2.algorithmSettings.algorithmType)){
  57                 /* Look up VE with RPM and MAP */
  58                 DerivedVars->VEMain = lookupMainTable(CoreVars->RPM, CoreVars->MAP, VETableMainLocationID);
  59                 /* This won't overflow until 512kPa or about 60psi of boost with 128% VE. */
  60                 DerivedVars->AirFlow = ((unsigned long)CoreVars->MAP * DerivedVars->VEMain) / VE(100);
  61                 /* Result is 450 - 65535 always. */
  62         }else if(fixedConfigs2.algorithmSettings.algorithmType == ALGO_ALPHA_N){
  63                 /* Look up Airflow with RPM and TPS */
  64                 DerivedVars->AirFlow = lookupMainTable(CoreVars->RPM, CoreVars->TPS, AirflowTableLocationID); /* Tuned air flow without density information */
  65         }else if(fixedConfigs2.algorithmSettings.algorithmType == ALGO_MAF){
  66                 DerivedVars->AirFlow = CoreVars->MAF; /* Just fix temperature at appropriate level to provide correct Lambda */
  67                 /// @todo TODO figure out what the correct "temperature" is to make MAF work correctly!
  68                 airInletTemp = DEGREES_C(20); // Room temperature?
  69         }else if(fixedConfigs2.algorithmSettings.algorithmType == ALGO_SD_AN_BLEND){
  70                 /* Look up VE with RPM and MAP */
  71                 DerivedVars->VEMain = lookupMainTable(CoreVars->RPM, CoreVars->MAP, VETableMainLocationID);
  72                 /* This won't overflow until 512kPa or about 60psi of boost with 128% VE. */
  73                 KeyUserDebugs.speedDensityAirFlow = ((unsigned long)CoreVars->MAP * DerivedVars->VEMain) / VE(100);
  74
  75                 /* Look up Airflow with RPM and TPS */
  76                 KeyUserDebugs.alphaNAirFlow = lookupMainTable(CoreVars->RPM, CoreVars->TPS, AirflowTableLocationID); /* Tuned air flow without density information */
  77
  78                 KeyUserDebugs.blendAlphaNPercent = lookupTwoDTableUS((twoDTableUS*)&TablesA.SmallTablesA.blendVersusRPMTable, CoreVars->RPM);
  79
  80                 unsigned short airflowSD = safeScale(KeyUserDebugs.speedDensityAirFlow, SHORTMAX - KeyUserDebugs.blendAlphaNPercent, SHORTMAX);
  81                 unsigned short airflowAN = safeScale(KeyUserDebugs.alphaNAirFlow, KeyUserDebugs.blendAlphaNPercent, SHORTMAX);
  82
  83                 DerivedVars->AirFlow = safeAdd(airflowSD, airflowAN);
  84         }else{ /* Default to no fuel delivery and error */
  85                 DerivedVars->AirFlow = 0;
  86         }
  87
  88
  89         /* This won't overflow until well past 125C inlet, 1.5 Lambda and fuel as dense as water */
  90         DerivedVars->densityAndFuel = (((unsigned long)((unsigned long)airInletTemp * DerivedVars->Lambda) / LAMBDA(1.0)) * fixedConfigs1.engineSettings.densityOfFuelAtSTP) / FUEL_DENSITY(FUEL_DENSITY_UNIT_FACTOR);
  91         /* Result is 7500 - 60000 always. TODO clean up the last item on the above line */
  92
  93         /* Divisors for air inlet temp and pressure :
  94          * #define airInletTempDivisor 100
  95          * #define airPressureDivisor 100
  96          * cancel each other out! all others are used. */
  97
  98         DerivedVars->BasePW = (bootFuelConst * DerivedVars->AirFlow) / DerivedVars->densityAndFuel;
  99
 100         /*&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&*/
 101
 102
 103
 104
 105         /*&&&&&&&&&&&&&&&&&&&&&&&&&&&& Apply All Corrections PCFC, ETE, IDT, TFC etc &&&&&&&&&&&&&&&&&&&&&&&&&&&*/
 106
 107         /* Apply the corrections after calculating */
 108         DerivedVars->EffectivePW = safeTrim(DerivedVars->BasePW, DerivedVars->TFCTotal);
 109         DerivedVars->EffectivePW = safeScale(DerivedVars->EffectivePW, DerivedVars->ETE, SHORT4TH);
 110
 111
 112 //      unsigned char channel; // the declaration of this variable is used in multiple loops below.
 113 //
 114 //      /* "Calculate" the individual fuel pulse widths */
 115 //      for(channel = 0; channel < INJECTION_CHANNELS; channel++){ /// @todo TODO make injector channels come from config, not defines.
 116 //              /* Add or subtract the per cylinder fuel trims */
 117 //              unsigned short channelPW;
 118 //              channelPW = safeScale(DerivedVars->EffectivePW, TablesB.SmallTablesB.perCylinderFuelTrims[channel]);
 119 //
 120 //              /* Add on the IDT to get the final value and put it into the array */
 121 //              //outputEventPulseWidthsMath[channel] = safeAdd(channelPW, DerivedVars->IDT); do not re-enable this without fixing it properly...
 122 //      }
 123
 124         // Make sure we don't have a PW if PW is supposed to be zero, ie, zero the IDT as well.
 125         if(!(DerivedVars->EffectivePW)){
 126                 DerivedVars->IDT = 0; // This also makes fuel and electrical duty work consistently in external apps.
 127         }
 128
 129         /* Reference PW for comparisons etc */
 130         DerivedVars->RefPW = safeAdd(DerivedVars->EffectivePW, DerivedVars->IDT);
 131         /*&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&*/
 132
 133 /// @todo accumulate errors such that we know what sort of PW WOULD have been requested and enable a "over duty cut" to protect boosted users with insufficient injector size on cold nights
 134
 135 /// TODO @todo FIXME part of to schedule or not to schedule should be : (masterPulseWidth > injectorMinimumPulseWidth)
 136 // IE, NOT in the decoders... KISS in the decoders. This is a hangover from (very) early decoder dev
 137
 138 //      for(channel = 0;channel < INJECTION_CHANNELS;channel++){ /// @todo TODO make injector channels come from config, not defines.
 139                 //injectorMainAdvances[channel] = IDT blah blah.
 140 //      }
 141
 142         /* "Calculate" the nominal total pulse width before per channel corrections */
 143         masterPulseWidth = safeAdd((DerivedVars->EffectivePW / fixedConfigs1.schedulingSettings.numberOfInjectionsPerEngineCycle), DerivedVars->IDT); // div by number of injections per cycle, configured above
 144         // but requires to know how big a cycle is, 1/4 1, 1/2, etc
 145
 146         // Note, conversions to address and then pointer are necessary to avoid error on direct cast
 147         // Cuts and limiters TODO move these to their own special place?
 148         // TODO Make source of threshold either struct or temp based curve for these
 149
 150         if(fixedConfigs1.cutAndLimiterSettings.cutsEnabled.IgnitionRPM){
 151                 unsigned short confirmedReenableThreshold = fixedConfigs1.cutAndLimiterSettings.IgnitionRPM.reenableThreshold;
 152                 if(confirmedReenableThreshold >= fixedConfigs1.cutAndLimiterSettings.IgnitionRPM.disableThreshold){
 153                         confirmedReenableThreshold = fixedConfigs1.cutAndLimiterSettings.IgnitionRPM.disableThreshold / 2;
 154                 }
 155                 if(CoreVars->RPM > fixedConfigs1.cutAndLimiterSettings.IgnitionRPM.disableThreshold){
 156                         ((ignitionCutFlags *)&KeyUserDebugs.ignitionCuts)->IgnitionRPM = 1;
 157                 }else if(CoreVars->RPM < confirmedReenableThreshold){
 158                         ((ignitionCutFlags *)&KeyUserDebugs.ignitionCuts)->IgnitionRPM = 0;
 159                 }
 160         }
 161
 162         if(fixedConfigs1.cutAndLimiterSettings.cutsEnabled.InjectionRPM){
 163                 unsigned short confirmedReenableThreshold = fixedConfigs1.cutAndLimiterSettings.InjectionRPM.reenableThreshold;
 164                 if(confirmedReenableThreshold >= fixedConfigs1.cutAndLimiterSettings.InjectionRPM.disableThreshold){
 165                         confirmedReenableThreshold = fixedConfigs1.cutAndLimiterSettings.InjectionRPM.disableThreshold / 2;
 166                 }
 167                 if(CoreVars->RPM > fixedConfigs1.cutAndLimiterSettings.InjectionRPM.disableThreshold){
 168                         ((injectionCutFlags *)&KeyUserDebugs.injectionCuts)->InjectionRPM = 1;
 169                 }else if(CoreVars->RPM < confirmedReenableThreshold){
 170                         ((injectionCutFlags *)&KeyUserDebugs.injectionCuts)->InjectionRPM = 0;
 171                 }
 172         }
 173
 174         // TODO add time based lock out as well as threshold based as threshold could re-enable too quickly
 175         if(fixedConfigs1.cutAndLimiterSettings.cutsEnabled.InjOverBoost || fixedConfigs1.cutAndLimiterSettings.cutsEnabled.IgnOverBoost){
 176                 unsigned short confirmedReenableThreshold = fixedConfigs1.cutAndLimiterSettings.OverBoost.reenableThreshold;
 177                 if(confirmedReenableThreshold >= fixedConfigs1.cutAndLimiterSettings.OverBoost.disableThreshold){
 178                         confirmedReenableThreshold = fixedConfigs1.cutAndLimiterSettings.OverBoost.disableThreshold / 2;
 179                 }
 180                 if(CoreVars->MAP > fixedConfigs1.cutAndLimiterSettings.OverBoost.disableThreshold){
 181                         ((injectionCutFlags *)&KeyUserDebugs.injectionCuts)->InjOverBoost = fixedConfigs1.cutAndLimiterSettings.cutsEnabled.InjOverBoost;
 182                         ((ignitionCutFlags *)&KeyUserDebugs.ignitionCuts)->IgnOverBoost = fixedConfigs1.cutAndLimiterSettings.cutsEnabled.IgnOverBoost;
 183                 }else if(CoreVars->MAP < confirmedReenableThreshold){
 184                         ((injectionCutFlags *)&KeyUserDebugs.injectionCuts)->InjOverBoost = 0;
 185                         ((ignitionCutFlags *)&KeyUserDebugs.ignitionCuts)->IgnOverBoost = 0;
 186                 }
 187         }
 188 }