src/inc/injectorISR.c

   1 /*      injectorISR.c
   2
   3         Copyright 2008 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 send them upstream to us at admin@diyefi.org
  21
  22         Thank you for choosing FreeEMS to run your engine! */
  23
  24 /* This code is identical between all 6 channels, and thus we only want one copy of it. The X in each macro will be replaced with the real deal appropriate for the channel it is used for at the time. */
  25
  26 /* Each channel performs the following actions
  27  *
  28  * 1    Clear its interrupt flag
  29  * 2    Record its start time
  30  * 3    Measure and record its latency
  31  * 4    Check to see if its just turned on
  32  * 4.1  Copy the channels pulse width to a local variable
  33  * 4.2  Determine the minimum pulse width based on code run time const and latency
  34  * 4.3  Clamp used pulsewidth inside min and max
  35  * 4.4  If used pulse width is larger than the current period of the engines cycle flag as always on
  36  * 4.5  Set the action to turn off
  37  * 4.6  Increment the time by pulse width
  38  * 4.7  If staging required, either, switch them on and sched to turn off, or sched to turn on
  39  * 5    Else it has just turned off
  40  * 5.1  If staged channel is still on, turn it off
  41  * 5.2  If(self schedule flagged) schedule the next start
  42  * 5.3  Else disable itself
  43  * 6    Calculate and record code run time
  44  * 7    Return
  45  */
  46
  47 void InjectorXISR(){
  48         /* Clear the interrupt flag for this channel */
  49         TFLG = injectorMainOnMasks[INJECTOR_CHANNEL_NUMBER];
  50
  51         /* Record the current time as start time */
  52         unsigned short TCNTStart = TCNT;
  53
  54         /* Record the edge time stamp from the IC register */
  55         unsigned short edgeTimeStamp = *injectorMainTimeRegisters[INJECTOR_CHANNEL_NUMBER];
  56
  57         /* Calculate and store the latency based on compare time and start time */
  58         injectorCodeLatencies[INJECTOR_CHANNEL_NUMBER] = TCNTStart - edgeTimeStamp;
  59
  60         /* If rising edge triggered this */
  61         if(PTIT & injectorMainOnMasks[INJECTOR_CHANNEL_NUMBER]){ // Stuff for switch on time
  62
  63                 /* Find out what max and min for pulse width are */
  64                 unsigned short localPulseWidth = injectorMainPulseWidthsRealtime[INJECTOR_CHANNEL_NUMBER];
  65                 unsigned short localMinimumPulseWidth = injectorSwitchOnCodeTime + injectorCodeLatencies[INJECTOR_CHANNEL_NUMBER];
  66
  67                 /* TODO *maybe* instead of checking min and increasing pulse, just force it straight off if diff between start and now+const is greater than desired pulsewidth */
  68
  69                 /* Ensure we dont go under minimum pulsewidth */
  70                 if(localPulseWidth < localMinimumPulseWidth){
  71                         localPulseWidth = localMinimumPulseWidth;
  72                 }/* else{ just use the value } */
  73
  74                 LongTime timeStamp;
  75
  76                 /* Install the low word */
  77                 timeStamp.timeShorts[1] = edgeTimeStamp;
  78                 /* Find out what our timer value means and put it in the high word */
  79                 if(TFLGOF && !(edgeTimeStamp & 0x8000)){ /* see 10.3.5 paragraph 4 of 68hc11 ref manual for details */
  80                         timeStamp.timeShorts[0] = timerExtensionClock + 1;
  81                 }else{
  82                         timeStamp.timeShorts[0] = timerExtensionClock;
  83                 }
  84
  85                 // store the end time for use in the scheduler
  86                 injectorMainEndTimes[INJECTOR_CHANNEL_NUMBER] = timeStamp.timeLong + localPulseWidth;
  87
  88                 /* Set the action for compare to switch off FIRST or it might inadvertently PWM the injector during opening... */
  89                 *injectorMainControlRegisters[INJECTOR_CHANNEL_NUMBER] &= injectorMainGoLowMasks[INJECTOR_CHANNEL_NUMBER];
  90
  91                 /* Set the time to turn off again */
  92                 *injectorMainTimeRegisters[INJECTOR_CHANNEL_NUMBER] += localPulseWidth;
  93
  94                 /* This is the point we actually want the time to, but because the code is so simple, it can't help but be a nice short time */
  95
  96                 /* If staged injection is required, switch on or schedule corresponding staged injector and remember that we did. */
  97                 if(coreStatusA & STAGED_REQUIRED){
  98                         if(fixedConfigs1.coreSettingsA & STAGED_START){
  99                                 /* Switch that channel on NOW */
 100                                 STAGEDPORT |= STAGEDXON;
 101                                 stagedOn |= STAGEDXON;
 102                         }else{
 103                                 /* Schedule the start at a later time */
 104                                 // TODO PIT scheduling of staged start
 105                         }
 106                 }
 107                 /* Calculate and store code run time */
 108                 injectorCodeOpenRuntimes[INJECTOR_CHANNEL_NUMBER] = TCNT - TCNTStart;
 109         }else{ // Stuff for switch off time
 110                 /* If we switched the staged injector on and it's still on, turn it off now. */
 111                 if(stagedOn & STAGEDXON){
 112                         STAGEDPORT &= STAGEDXOFF;
 113                         stagedOn &= STAGEDXOFF;
 114                 }
 115
 116                 /* Set the action for compare to switch on and the time to next start time, clear the self timer flag */
 117                 if(selfSetTimer & injectorMainOnMasks[INJECTOR_CHANNEL_NUMBER]){
 118                         *injectorMainTimeRegisters[INJECTOR_CHANNEL_NUMBER] = injectorMainStartTimesHolding[INJECTOR_CHANNEL_NUMBER];
 119                         *injectorMainControlRegisters[INJECTOR_CHANNEL_NUMBER] |= injectorMainGoHighMasks[INJECTOR_CHANNEL_NUMBER];
 120                         selfSetTimer &= injectorMainOffMasks[INJECTOR_CHANNEL_NUMBER];
 121                 }else{
 122                         // Disable interrupts and actions incase the period from this end to the next start is long (saves cpu)
 123                         TIE &= injectorMainOffMasks[INJECTOR_CHANNEL_NUMBER];
 124                         *injectorMainControlRegisters[INJECTOR_CHANNEL_NUMBER] &= injectorMainDisableMasks[INJECTOR_CHANNEL_NUMBER];
 125                 }
 126                 /* Calculate and store code run time */
 127                 injectorCodeCloseRuntimes[INJECTOR_CHANNEL_NUMBER] = TCNT - TCNTStart;
 128         }
 129 }