Simple.c File Reference

Reads any signal that is once per cylinder. More...

#include "inc/freeEMS.h"
#include "inc/interrupts.h"
#include "inc/utils.h"

Include dependency graph for Simple.c:

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Defines
#define	ticksPerMinute   75000000
Functions
void	PrimaryRPMISR ()
void	SecondaryRPMISR ()
	Use the rising and falling edges...................

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Detailed Description

Reads any signal that is once per cylinder.

This file contains the two interrupt service routines required for to build cleanly. However, only the first one is used due to the simple nature of it.

The functional ISR just blindly injects fuel for every input it receives. Thus a perfectly clean input is absolutely essential at this time.

Supported engines include: B230F

Author:

Fred Cooke

Note:

Even though I ran my US road trip car on this exact code, I don't recommend it unless you REALLY know what you are doing!

Definition in file Simple.c.

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Define Documentation

#define ticksPerMinute   75000000

Referenced by PrimaryRPMISR().

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Function Documentation

void PrimaryRPMISR

(

void

)

Primary RPM ISR

Schedule events : Blindly start fuel pulses for each and every input pulse.

Sample ADCs : Grab a unified set of ADC readings at one time in a consistent crank location to eliminate engine cycle dependent noise. Set flag stating that New pulse, advance, etc should be calculated.

Author:

Fred Cooke

Warning:

These are for testing and demonstration only, not suitable for driving with just yet.

Todo:

TODO make this code more general and robust such that it can be used for real simple applications

Todo:

TODO discard narrow ones! test for tooth width and tooth period the width should be based on how the hardware is setup. IE the LM1815 is adjusted to have a pulse output of a particular width. This noise filter should be matched to that width as should the hardware filter.

Definition at line 68 of file Simple.c.

References ADCArrays, CALC_FUEL_IGN, Clocks, coreStatusA, Counters, engineCyclePeriod, injectorMainControlRegisters, injectorMainEnableMasks, injectorMainEndTimes, injectorMainOnMasks, injectorMainStartTimesHolding, injectorMainTimeRegisters, injectorMinimumPulseWidth, injectorSwitchOffCodeTime, ISRLatencyVars, lastPrimaryPulseTimeStamp, LONGHALF, masterPulseWidth, mathSampleTimeStampRecord, PORTJ, PRIMARY_SYNC, ISRLatencyVar::primaryInputLatency, RuntimeVar::primaryInputLeadingRuntime, RuntimeVar::primaryInputTrailingRuntime, primaryLeadingEdgeTimeStamp, Counter::primaryTeethSeen, PTIT, RPMRecord, RuntimeVars, sampleEachADC(), selfSetTimer, Counter::syncedADCreadings, TC0, TCNT, TFLG, TFLGOF, ticksPerMinute, TIE, timeBetweenSuccessivePrimaryPulses, LongTime::timeLong, Clock::timeoutADCreadingClock, timerExtensionClock, LongTime::timeShorts, totalAngleAfterReferenceInjection, and trailingEdgeSecondaryRPMInputCodeTime.

                    {
    /* Clear the interrupt flag for this input compare channel */
    TFLG = 0x01;

    /* Save all relevant available data here */
    unsigned short codeStartTimeStamp = TCNT;       /* Save the current timer count */
    unsigned short edgeTimeStamp = TC0;             /* Save the edge time stamp */
    unsigned char PTITCurrentState = PTIT;          /* Save the values on port T regardless of the state of DDRT */

    // set as synced for volvo always as loss of sync not actually possible
    coreStatusA |= PRIMARY_SYNC;

    /* Calculate the latency in ticks */
    ISRLatencyVars.primaryInputLatency = codeStartTimeStamp - edgeTimeStamp;

    if(PTITCurrentState & 0x01){
        /* Echo input condition on J7 */
        PORTJ |= 0x80;

        Counters.primaryTeethSeen++;

        LongTime timeStamp;

        /* Install the low word */
        timeStamp.timeShorts[1] = edgeTimeStamp;
        /* Find out what our timer value means and put it in the high word */
        if(TFLGOF && !(edgeTimeStamp & 0x8000)){ /* see 10.3.5 paragraph 4 of 68hc11 ref manual for details */
            timeStamp.timeShorts[0] = timerExtensionClock + 1;
        }else{
            timeStamp.timeShorts[0] = timerExtensionClock;
        }

        // temporary data from inputs
        primaryLeadingEdgeTimeStamp = timeStamp.timeLong;
        timeBetweenSuccessivePrimaryPulses = primaryLeadingEdgeTimeStamp - lastPrimaryPulseTimeStamp;
        lastPrimaryPulseTimeStamp = primaryLeadingEdgeTimeStamp;

#define ticksPerMinute   75000000 // this is correct.

        *RPMRecord = (unsigned short) (ticksPerMinute / timeBetweenSuccessivePrimaryPulses);

        // TODO sample ADCs on teeth other than that used by the scheduler in order to minimise peak run time and get clean signals
        sampleEachADC(ADCArrays);
        Counters.syncedADCreadings++;
        *mathSampleTimeStampRecord = TCNT;

        /* Set flag to say calc required */
        coreStatusA |= CALC_FUEL_IGN;

        /* Reset the clock for reading timeout */
        Clocks.timeoutADCreadingClock = 0;

        if(masterPulseWidth > injectorMinimumPulseWidth){ // use reference PW to decide. spark needs moving outside this area though TODO
            /* Determine if half the cycle is bigger than short-max */
            unsigned short maxAngleAfter;
            if((engineCyclePeriod >> 1) > 0xFFFF){
                maxAngleAfter = 0xFFFF;
            }else{
                maxAngleAfter = (unsigned short)(engineCyclePeriod >> 1);
            }

            /* Check advance to ensure it is less than 1/2 of the previous engine cycle and more than codetime away */
            unsigned short advance;
            if(totalAngleAfterReferenceInjection > maxAngleAfter){ // if too big, make it max
                advance = maxAngleAfter;
            }else if(totalAngleAfterReferenceInjection < trailingEdgeSecondaryRPMInputCodeTime){ // if too small, make it min
                advance = trailingEdgeSecondaryRPMInputCodeTime;
            }else{ // else use it as is
                advance = totalAngleAfterReferenceInjection;
            }

            // determine the long and short start times
            unsigned short startTime = edgeTimeStamp + advance;
            unsigned long startTimeLong = timeStamp.timeLong + advance;

            /* Determine the channels to schedule */
            unsigned char fuelChannel = 0;//(primaryPulsesPerSecondaryPulse / 2) - 1;

            // determine whether or not to reschedule
            unsigned char reschedule = 0;
            unsigned long diff = startTimeLong - (injectorMainEndTimes[fuelChannel] + injectorSwitchOffCodeTime);
            if(diff > LONGHALF){
                reschedule = 1; // http://www.diyefi.org/forum/viewtopic.php?f=8&t=57&p=861#p861
            }

            // schedule the appropriate channel
            if(!(*injectorMainControlRegisters[fuelChannel] & injectorMainEnableMasks[fuelChannel]) || reschedule){ /* If the timer isn't still running, or if its set too long, set it to start again at the right time soon */
                *injectorMainControlRegisters[fuelChannel] |= injectorMainEnableMasks[fuelChannel];
                *injectorMainTimeRegisters[fuelChannel] = startTime;
                TIE |= injectorMainOnMasks[fuelChannel];
                TFLG = injectorMainOnMasks[fuelChannel];
            }else{
                injectorMainStartTimesHolding[fuelChannel] = startTime;
                selfSetTimer |= injectorMainOnMasks[fuelChannel]; // setup a bit to let the timer interrupt know to set its own new start from a var
            }
        }
        RuntimeVars.primaryInputLeadingRuntime = TCNT - codeStartTimeStamp;
    }else{
        PORTJ &= 0x7F;
        RuntimeVars.primaryInputTrailingRuntime = TCNT - codeStartTimeStamp;
    }
}

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void SecondaryRPMISR

(

void

)

Use the rising and falling edges...................

Secondary RPM ISR

Unused in this decoder.

Todo:

TODO discard narrow ones! test for tooth width and tooth period the width should be based on how the hardware is setup. IE the LM1815 is adjusted to have a pulse output of a particular width. This noise filter should be matched to that width as should the hardware filter.

Definition at line 176 of file Simple.c.

References Counters, ISRLatencyVars, lastSecondaryPulseLeadingTimeStamp, lastSecondaryPulseTrailingTimeStamp, lengthOfSecondaryLowPulses, PORTJ, PTIT, ISRLatencyVar::secondaryInputLatency, Counter::secondaryTeethSeen, TC1, TCNT, TFLG, TFLGOF, LongTime::timeLong, timerExtensionClock, and LongTime::timeShorts.

                      {
    /* Clear the interrupt flag for this input compare channel */
    TFLG = 0x02;

    /* Save all relevant available data here */
    unsigned short codeStartTimeStamp = TCNT;       /* Save the current timer count */
    unsigned short edgeTimeStamp = TC1;             /* Save the timestamp */
    unsigned char PTITCurrentState = PTIT;          /* Save the values on port T regardless of the state of DDRT */
//  unsigned short PORTS_BACurrentState = PORTS_BA; /* Save ignition output state */

    /* Calculate the latency in ticks */
    ISRLatencyVars.secondaryInputLatency = codeStartTimeStamp - edgeTimeStamp;

    LongTime timeStamp;

    /* Install the low word */
    timeStamp.timeShorts[1] = edgeTimeStamp;
    /* Find out what our timer value means and put it in the high word */
    if(TFLGOF && !(edgeTimeStamp & 0x8000)){ /* see 10.3.5 paragraph 4 of 68hc11 ref manual for details */
        timeStamp.timeShorts[0] = timerExtensionClock + 1;
    }else{
        timeStamp.timeShorts[0] = timerExtensionClock;
    }

    /* The LM1815 variable reluctance sensor amplifier allows the output to be
     * pulled high starting at the center of a tooth. So, what we see as the
     * start of a tooth is actually the centre of a physical tooth. Because
     * tooth shape, profile and spacing may vary this is the only reliable edge
     * for us to schedule from, hence the trailing edge code is very simple.
     */
    if(PTITCurrentState & 0x02){
        // echo input condition
        PORTJ |= 0x40;

        Counters.secondaryTeethSeen++;

        /* leading code
         *
         * subtract lastTrailing from currentLeading
         * record currentLeading as lastLeading
         *
         * record pw as highDuration
         */
        lengthOfSecondaryLowPulses = timeStamp.timeLong - lastSecondaryPulseTrailingTimeStamp;
        lastSecondaryPulseLeadingTimeStamp = timeStamp.timeLong;
    }else{

        /* trailing code
         *
         * subtract lastLeading from currentTrailing
         * record currentTrailing as lastTrailing
         *
         * record pw as lowDuration
         */
//      lengthOfSecondaryHighPulses = timeStamp.timeLong - lastSecondaryPulseLeadingTimeStamp;
        lastSecondaryPulseTrailingTimeStamp = timeStamp.timeLong;

        PORTJ &= 0xBF;
    }
}