derivedVarsGenerator.c

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/* FreeEMS - the open source engine management system
 *
 * Copyright 2008-2013 Fred Cooke
 *
 * This file is part of the FreeEMS project.
 *
 * FreeEMS software 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.
 *
 * FreeEMS software 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 any FreeEMS software.  If not, see http://www.gnu.org/licenses/
 *
 * We ask that if you make any changes to this file you email them upstream to
 * us at admin(at)diyefi(dot)org or, even better, fork the code on github.com!
 *
 * Thank you for choosing FreeEMS to run your engine!
 */


/** @file
 *
 * @ingroup measurementsAndCalculations
 *
 * @brief Generate the derived variables.
 *
 * Second level variables are derived from the core variables and generated here.
 */


#define DERIVEDVARSGENERATOR_C
#include "inc/freeEMS.h"
#include "inc/commsCore.h"
#include "inc/tableLookup.h"
#include "inc/derivedVarsGenerator.h"
#include "inc/locationIDs.h"
#include "inc/decoderInterface.h"


/**
 * Use core variables to lookup and calculate the derived variables. This
 * function uses the core variables to lookup and calculate further second
 * order variables such as load, VE, Lamdda, Transient fuel correction, engine
 * temperature enrichment, Injector dead time, etc.
 */
void generateDerivedVars(){
    /* Determine load based on options */
    if(!(fixedConfigs2.algorithmSettings.loadType)){ /* Use MAP as load */
        DerivedVars->LoadMain = CoreVars->MAP;
    }else if(fixedConfigs2.algorithmSettings.loadType == LOAD_TPS){ /* Use TPS as load */
        DerivedVars->LoadMain = CoreVars->TPS;
    }else if(fixedConfigs2.algorithmSettings.loadType == LOAD_AAP){ /* Use AAP corrected MAP as load */
        DerivedVars->LoadMain = ((unsigned long)CoreVars->MAP * CoreVars->AAP) / KPA(100);
        // TODO add maf calc load option here
    }else{ /* Default to MAP, but throw error */
        DerivedVars->LoadMain = CoreVars->MAP;
    }


    /* Look up target Lambda with RPM and Load */
    DerivedVars->Lambda = lookupMainTable(CoreVars->RPM, DerivedVars->LoadMain, LambdaTableLocationID);


    /* Look up injector dead time with battery voltage */
    DerivedVars->IDT = lookupTwoDTableUS((twoDTableUS*)&TablesA.SmallTablesA.injectorDeadTimeTable, CoreVars->BRV);

    if(!(fixedConfigs2.algorithmSettings.dwellType)){
        DerivedVars->Dwell = lookupTwoDTableUS((twoDTableUS*)&TablesA.SmallTablesA.dwellDesiredVersusVoltageTable, CoreVars->BRV);
    }else if(fixedConfigs2.algorithmSettings.dwellType == DWELL_RPM){
        DerivedVars->Dwell = lookupTwoDTableUS((twoDTableUS*)&TablesA.SmallTablesA.dwellVersusRPMTable, CoreVars->RPM);
    }else if(fixedConfigs2.algorithmSettings.dwellType == DWELL_FIXED){
        DerivedVars->Dwell = fixedConfigs2.algorithmSettings.dwellFixedPeriod;
    }else{
        DerivedVars->Dwell = 0;
    }

    unsigned long tempAdvance = ANGLE_FACTOR * (unsigned long)lookupMainTable(CoreVars->RPM, DerivedVars->LoadMain, IgnitionAdvanceTableMainLocationID);
    DerivedVars->Advance = (unsigned short)(tempAdvance / 1024); // This calculation will change when the timing tables get shrunk to a more reasonable 8 bit size with appropriate scaling
    // Move this magic number to an appropriate place and/or refactor timing calcs/values/etc

/// @todo TODO make generic!!!!
// to go generic we need:
// angle between ignition events (if have tpd) (or total angle and number of events)
// max % dwell
// minimum spark time
// a setting to choose which behaviour (don't limit/% dwell limit/min spark time/other?)
#if CONFIG == HOTEL_ID
    /// @bug hack for hyundai! 135 = 3/4 of 180 = one cycle...
    unsigned long threeQuartersOfAvailableTime = ((unsigned long)CoreVars->DRPM * 135 * ANGLE_FACTOR) / ticks_per_degree_multiplier;
    if(DerivedVars->Dwell > threeQuartersOfAvailableTime){
        DerivedVars->Dwell = threeQuartersOfAvailableTime;
    }
#endif

    /* Look up the engine temperature enrichment percentage with temperature */
    DerivedVars->ETE = lookupTwoDTableUS((twoDTableUS*)&TablesA.SmallTablesA.engineTempEnrichmentTablePercent, CoreVars->CHT);
    /* TODO The above needs some careful thought put into it around different loads and correction effects. */


    /* Calculate the Transient Fuel Correction */
    if(TRUE /*WWTFC*/){ /* Do ONLY WW correction if enabled */
        // Do ww stuff, maybe pre done via RTC/RTI for consistent period?
        DerivedVars->TFCTotal = 0; /* TODO replace with real code */
    }else if(FALSE /*STDTFC*/){ /* Do any combination of standard approximate methods */
        /* Initialse the variable as a base */
        DerivedVars->TFCTotal = 0;
        /* Based on the rate of change of MAP and some history/taper time */
        if(FALSE /*MAPTFC*/){
            // Do MAP based
            DerivedVars->TFCTotal += 0;
        }

        /* Based on the rate of change of TPS and some history/taper time */
        if(FALSE /*TPSTFC*/){
            // Do TPS based
            DerivedVars->TFCTotal += 0;
        }

        /* Based on the rate of change of RPM and some history/taper time */
        if(FALSE /*RPMTFC*/){
            // Do RPM based
            DerivedVars->TFCTotal += 0;
        }
    }else{ /* Default to no correction */
        DerivedVars->TFCTotal = 0;
        /* Don't throw error as correction may not be required */
    }
}