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Improvement to the way that timers are forced to overflow, which should allow PPM on CC3D to work properly.

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This commit is contained in:
Ben Hitchcock 2014-11-30 08:08:34 +08:00
parent c0ed21a818
commit 5096873ab1
2 changed files with 13 additions and 14 deletions
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21
src/main/drivers/pwm_output.c
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@ -37,7 +37,7 @@ typedef void (*pwmWriteFuncPtr)(uint8_t index, uint16_t value); // function poi
typedef struct {
volatile timCCR_t *ccr;
volatile timCNT_t *cnt;
volatile TIM_TypeDef *tim;
uint16_t period;
pwmWriteFuncPtr pwmWritePtr;
} pwmOutputPort_t;
@ -46,7 +46,6 @@ static pwmOutputPort_t pwmOutputPorts[MAX_PWM_OUTPUT_PORTS];
static pwmOutputPort_t *motors[MAX_PWM_MOTORS];
static pwmOutputPort_t *servos[MAX_PWM_SERVOS];
static volatile uint16_t* lastCounterPtr;
#define PWM_BRUSHED_TIMER_MHZ 8
@ -120,7 +119,7 @@ static pwmOutputPort_t *pwmOutConfig(const timerHardware_t *timerHardware, uint8
break;
}
p->period = period;
p->cnt = &timerHardware->tim->CNT;
p->tim = timerHardware->tim;
return p;
}
@ -144,22 +143,22 @@ void pwmWriteMotor(uint8_t index, uint16_t value)
void pwmFinishedWritingMotors(uint8_t numberMotors)
{
uint8_t index;
volatile TIM_TypeDef *lastTimerPtr = NULL;
if(feature(FEATURE_ONESHOT125)){
for(index = 0; index < numberMotors; index++){
// Force the counter to overflow if it's the first motor to output, or if we change timers
if((index == 0) || (motors[index]->cnt != lastCounterPtr)){
lastCounterPtr = motors[index]->cnt;
*motors[index]->cnt = 0xfffe;
// Force the timer to overflow if it's the first motor to output, or if we change timers
if(motors[index]->tim != lastTimerPtr){
lastTimerPtr = motors[index]->tim;
// Force an overflow by setting the UG bit
motors[index]->tim->EGR |= 0x0001;
}
}
// Wait until the timers have overflowed (should take less than 0.125 uS)
while(*motors[numberMotors - 1]->cnt >= 0xfffe){
}
// Set the compare register to 0, which stops the output pulsing if the timer overflows before the main loop completes again.
// This compare register will be set to the output value on the next main loop.
for(index = 0; index < numberMotors; index++){