utils.c File Reference

Utility functions only. More...

#include "inc/freeEMS.h"
#include "inc/commsISRs.h"
#include "inc/utils.h"
#include <string.h>

Include dependency graph for utils.c:

Go to the source code of this file.

Defines
#define	UTILS_C
Functions
unsigned short	safeAdd (unsigned short addend1, unsigned short addend2)
	Add two unsigned shorts safely.
unsigned short	safeTrim (unsigned short addend1, signed short addend2)
	Add two unsigned shorts safely.
unsigned short	safeScale (unsigned short baseValue, unsigned short scaler)
	Scale without overflow.
void	setupPagedRAM (unsigned char bool)
	Setup tune switching.
void	resetToNonRunningState ()
	Reset key state.
void	adjustPWM ()
	Demonstrate PWM.
void	sampleEachADC (ADCArray *Arrays)
	Read ADCs one at a time.
void	sampleLoopADC (ADCArray *Arrays)
	Read ADCs in a loop.
void	sleep (unsigned short ms)
	Sleep for X milli seconds.
void	sleepMicro (unsigned short us)
	Sleep for X micro seconds.
unsigned char	checksum (unsigned char *block, unsigned short length)
	Simple checksum.
unsigned short	stringCopy (unsigned char *dest, unsigned char *source)
	Homebrew strcpy().
unsigned short	compare (unsigned char *original, unsigned char *toCheck, unsigned short length)

---

Detailed Description

Utility functions only.

General purpose utility functions that are used in various places throughout the code base. Functions should only be placed here if they are not strongly related to any other set of functionality.

Author:

Fred Cooke

Definition in file utils.c.

---

Define Documentation

#define UTILS_C

Definition at line 39 of file utils.c.

---

Function Documentation

void adjustPWM

(

void

)

Demonstrate PWM.

Demonstrate basic PWM module usage by setting duty to scaled ADC inputs.

Author:

Fred Cooke

Definition at line 174 of file utils.c.

References ATD0DR0, ATD0DR1, ATD0DR2, ATD0DR3, ATD0DR4, ATD0DR5, ATD0DR6, ATD0DR7, PWMDTY0, PWMDTY1, PWMDTY2, PWMDTY3, PWMDTY4, PWMDTY5, PWMDTY6, and PWMDTY7.

Referenced by main().

                {
    PWMDTY0 = ATD0DR0 >> 2; // scale raw adc to a duty
    PWMDTY1 = ATD0DR1 >> 2; // scale raw adc to a duty
    PWMDTY2 = ATD0DR2 >> 2; // scale raw adc to a duty
    PWMDTY3 = ATD0DR3 >> 2; // scale raw adc to a duty
    PWMDTY4 = ATD0DR4 >> 2; // scale raw adc to a duty
    PWMDTY5 = ATD0DR5 >> 2; // scale raw adc to a duty
    PWMDTY6 = ATD0DR6 >> 2; // scale raw adc to a duty
    PWMDTY7 = ATD0DR7 >> 2; // scale raw adc to a duty (user led instead at the moment, see init)
}

unsigned char checksum	(	unsigned char *	block,
		unsigned short	length
	)

Simple checksum.

Generate a simple additive checksum for a block of data.

Author:

Fred Cooke

Parameters:

	block	a pointer to a memory region to checksum.
	length	how large the memory region to checksum is.

Returns:

a simple additive checksum.

Definition at line 309 of file utils.c.

Referenced by checksumAndSend().

                                                                   {
    unsigned char sum = 0;
    while (length-- > 0){
        sum += *block++;
    }
    return sum;
}

unsigned short compare	(	unsigned char *	original,
		unsigned char *	toCheck,
		unsigned short	length
	)

Returns:

a one based index of the failure point

Note:

this will return a positive result with bad data in the last position of a maximum sized block

Definition at line 343 of file utils.c.

Referenced by decodePacketAndRespond(), and initXgate().

                                                                                              {
    unsigned short i;
    for(i=0;i<length;i++){
        if(original[i] != toCheck[i]){
            return i + 1; // zero = success
        }
    }
    return 0;
}

void resetToNonRunningState

(

void

)

Reset key state.

Reset all important variables to their non-running state.

Todo:

TODO bring this up to date and/or find a better way to do it.

Author:

Fred Cooke

Definition at line 151 of file utils.c.

References CLEAR_PRIMARY_SYNC, coreStatusA, engineCyclePeriod, RPM0, RPM1, and ticksPerCycleAtOneRPM.

Referenced by main().

                             {
    /* Reset RPM to zero */
    RPM0 = 0;
    RPM1 = 0;

    /* Ensure tacho reads lowest possible value */
    engineCyclePeriod = ticksPerCycleAtOneRPM;

    /* Clear all sync flags to lost state */
    //coreStatusA &= CLEAR_RPM_VALID;
    coreStatusA &= CLEAR_PRIMARY_SYNC;
    //coreStatusA &= CLEAR_SECONDARY_SYNC;

    // TODO more stuff needs resetting here, but only critical things.
}

unsigned short safeAdd	(	unsigned short	addend1,
		unsigned short	addend2
	)

Add two unsigned shorts safely.

This will either return short max or the sum of the two arguments.

Author:

Fred Cooke

Parameters:

	addend1
	addend2

Definition at line 55 of file utils.c.

References SHORTMAX.

Referenced by calculateFuelAndIgnition().

                                                                      {
    if((SHORTMAX - addend1) > addend2){
        return addend1 + addend2;
    }else{
        return SHORTMAX;
    }
}

unsigned short safeScale	(	unsigned short	baseValue,
		unsigned short	scaler
	)

Scale without overflow.

Takes a base value and a scaler where 0x8000/32768 means 100%, 0 means 0% and 0xFFFF/65535 means 200%, and returns the baseValue multiplied, in effect, by the resulting percentage figure.

Author:

Fred Cooke

Parameters:

	baseValue
	scaler

Definition at line 104 of file utils.c.

References SHORTHALF, and SHORTMAX.

Referenced by calculateFuelAndIgnition().

                                                                         {
    /* Perform the scaling */
    unsigned short scaled = ((unsigned long)baseValue * scaler) / SHORTHALF;

    /* If the trim is greater than 100% then the trimmedPW MUST be larger */
    /* If it's less than 100% it can't have overflowed */        /* If it's not larger, it overflowed */
    if((scaler > SHORTHALF) && (baseValue > scaled)){
        return SHORTMAX;
    }else{
        return scaled;
    }
}

unsigned short safeTrim	(	unsigned short	addend1,
		signed short	addend2
	)

Add two unsigned shorts safely.

This will either return short max or the sum of the two arguments.

Author:

Fred Cooke

Parameters:

	addend1
	addend2

Definition at line 73 of file utils.c.

References SHORTMAX.

Referenced by calculateFuelAndIgnition().

                                                                     {

    if(addend2 < 0){
        if(addend1 > -addend2){
            return addend1 + addend2;
        }else{
            return 0;
        }
    }else if(addend2 > 0){
        if(addend2 < (SHORTMAX - addend1)){
            return addend1 + addend2;
        }else{
            return SHORTMAX;
        }
    }else{
        return addend1;
    }
}

void sampleEachADC

(

ADCArray *

Arrays

)

Read ADCs one at a time.

Read ADCs into the correct bank one at a time by name.

Author:

Fred Cooke

Parameters:

Arrays

a pointer to an ADCArray struct to store ADC values in.

Definition at line 194 of file utils.c.

References ADCArray::AAP, ATD0DR0, ATD0DR1, ATD0DR2, ATD0DR3, ATD0DR4, ATD0DR5, ATD0DR6, ATD0DR7, ATD1DR0, ATD1DR1, ATD1DR2, ATD1DR3, ATD1DR4, ATD1DR5, ATD1DR6, ATD1DR7, ADCArray::BRV, ADCArray::CHT, ADCArray::EGO, ADCArray::EGO2, ADCArray::IAP, ADCArray::IAT, ADCArray::MAF, ADCArray::MAP, ADCArray::MAT, ADCArray::SpareADC3, ADCArray::SpareADC4, ADCArray::SpareADC5, ADCArray::SpareADC6, ADCArray::SpareADC7, and ADCArray::TPS.

Referenced by main(), and PrimaryRPMISR().

                                    {
    /* ATD0 */
    Arrays->IAT = ATD0DR0;
    Arrays->CHT = ATD0DR1;
    Arrays->TPS = ATD0DR2;
    Arrays->EGO = ATD0DR3;
    Arrays->MAP = ATD0DR4;
    Arrays->AAP = ATD0DR5;
    Arrays->BRV = ATD0DR6;
    Arrays->MAT = ATD0DR7;

    /* ATD1 */
    Arrays->EGO2 = ATD1DR0;
    Arrays->IAP = ATD1DR1;
    Arrays->MAF = ATD1DR2;
    Arrays->SpareADC3 = ATD1DR3;
    Arrays->SpareADC4 = ATD1DR4;
    Arrays->SpareADC5 = ATD1DR5;
    Arrays->SpareADC6 = ATD1DR6;
    Arrays->SpareADC7 = ATD1DR7;
}

void sampleLoopADC

(

ADCArray *

Arrays

)

Read ADCs in a loop.

Read ADCs into the correct bank in a loop using pointers.

Author:

Fred Cooke

Parameters:

Arrays

a pointer to an ADCArray struct to store ADC values in.

Todo:

TODO this needs to be split into two loops one for the small block and one for the big one for the future chips.

Definition at line 225 of file utils.c.

References ATD0_BASE, ATD1_BASE, and DVUSP.

                                    {
    // get the address of the ADC array
    unsigned short addr = (unsigned short)Arrays;

    //sendUS(addr);
    unsigned char loop;
    /* (value of((address of ADCArrays struct) + (offset to start of bank(0 or half struct length)) + (offset to particular ADC (loopcounter * 4)) + (offset to correct element(0 or 2)))) =
     * (value of((address of ARRAY block) + (loop counter * 2))) */

    for(loop=0;loop<16;loop += 2){
        /* Do the first block */
        DVUSP(addr + loop) = DVUSP(ATD0_BASE + loop);

        /* Do the second block */
        DVUSP(addr + 16 + loop) = DVUSP(ATD1_BASE + loop);
    }
}

void setupPagedRAM

(

unsigned char

bool

)

Setup tune switching.

Place the correct set of tables in RAM based on a boolean parameter

Todo:

TODO change parameter style to be a pointer to a register and a mask?

Author:

Fred Cooke

Parameters:

bool

which set of data to enable.

Definition at line 128 of file utils.c.

References currentFuelRPage, currentTimeRPage, currentTuneRPage, RPAGE, RPAGE_FUEL_ONE, RPAGE_FUEL_TWO, RPAGE_TIME_ONE, RPAGE_TIME_TWO, RPAGE_TUNE_ONE, and RPAGE_TUNE_TWO.

Referenced by initAllPagedRAM().

                                      {
    if(bool){
        currentFuelRPage = RPAGE_FUEL_ONE;
        currentTimeRPage = RPAGE_TIME_ONE;
        currentTuneRPage = RPAGE_TUNE_ONE;
    }else{
        currentFuelRPage = RPAGE_FUEL_TWO;
        currentTimeRPage = RPAGE_TIME_TWO;
        currentTuneRPage = RPAGE_TUNE_TWO;
    }

    RPAGE = currentTuneRPage;
}

void sleep

(

unsigned short

ms

)

Sleep for X milli seconds.

Run in a nested loop repeatedly for X milli seconds.

Author:

Fred Cooke

Parameters:

ms

the number of milli seconds to kill

Definition at line 270 of file utils.c.

Referenced by initConfiguration().

                             {
    unsigned short j, k;
    for(j=0;j<ms;j++){
        for(k=0;k<5714;k++){
        }
    }
}

void sleepMicro

(

unsigned short

us

)

Sleep for X micro seconds.

Run in a nested loop repeatedly for X micro seconds.

Note:

Very approximate...

Author:

Fred Cooke

Parameters:

us

the number of micro seconds to kill

Definition at line 289 of file utils.c.

Referenced by main().

                                  {
    unsigned short j, k;
    for(j=0;j<us;j++){
        for(k=0;k<6;k++){
        }
    }
}

unsigned short stringCopy	(	unsigned char *	dest,
		unsigned char *	source
	)

Homebrew strcpy().

strcpy() wouldn't compile for me for some reason so I wrote my own.

Author:

Fred Cooke

Parameters:

	dest	where to copy the null terminated string to.
	source	where to copy the null terminated string from.

Returns:

the length of the string copied.

Definition at line 329 of file utils.c.

Referenced by sendDebugInternal().

                                                                     {
    short length = -1;
    do {
        *dest++ = *source++;
        length++;
    } while(*(source-1) != 0);
    return (unsigned short) length;
}