static void ppmEdgeCallback(timerCCHandlerRec_t* cbRec, captureCompare_t capture)
{
UNUSED(cbRec);
ppmISREvent(SOURCE_EDGE, capture);
int32_t i;
uint32_t previousTime = ppmDev.currentTime;
uint32_t previousCapture = ppmDev.currentCapture;
/* Grab the new count */
uint32_t currentTime = capture;
/* Convert to 32-bit timer result */
currentTime += ppmDev.largeCounter;
if (capture < previousCapture) {
if (ppmDev.overflowed) {
currentTime += PPM_TIMER_PERIOD;
}
}
// Divide by 8 if Oneshot125 is active and this is a CC3D board
currentTime = currentTime >> ppmCountShift;
/* Capture computation */
if (currentTime > previousTime) {
ppmDev.deltaTime = currentTime - (previousTime + (ppmDev.overflowed ? (PPM_TIMER_PERIOD >> ppmCountShift) : 0));
} else {
static void ppmOverflowCallback(timerOvrHandlerRec_t* cbRec, captureCompare_t capture)
{
UNUSED(cbRec);
ppmISREvent(SOURCE_OVERFLOW, capture);
ppmDev.largeCounter += capture + 1;
if (capture == PPM_TIMER_PERIOD - 1) {
ppmDev.overflowed = true;
}
}
static void ppmEdgeCallback(timerCCHandlerRec_t* cbRec, captureCompare_t capture)
{
UNUSED(cbRec);
ppmISREvent(SOURCE_EDGE, capture);
int32_t i;
uint32_t previousTime = ppmDev.currentTime;
uint32_t previousCapture = ppmDev.currentCapture;
/* Grab the new count */
uint32_t currentTime = capture;
/* Convert to 32-bit timer result */
currentTime += ppmDev.largeCounter;
if (capture < previousCapture) {
if (ppmDev.overflowed) {
currentTime += PPM_TIMER_PERIOD;
}
}
// Divide value if Oneshot, Multishot or brushed motors are active and the timer is shared
currentTime = currentTime / ppmCountDivisor;
/* Capture computation */
if (currentTime > previousTime) {
ppmDev.deltaTime = currentTime - (previousTime + (ppmDev.overflowed ? (PPM_TIMER_PERIOD / ppmCountDivisor) : 0));
} else {
ppmDev.deltaTime = (PPM_TIMER_PERIOD / ppmCountDivisor) + currentTime - previousTime;
}
ppmDev.overflowed = false;
/* Store the current measurement */
ppmDev.currentTime = currentTime;
ppmDev.currentCapture = capture;
/* Sync pulse detection */
if (ppmDev.deltaTime > PPM_IN_MIN_SYNC_PULSE_US) {
if (ppmDev.pulseIndex == ppmDev.numChannelsPrevFrame
&& ppmDev.pulseIndex >= PPM_IN_MIN_NUM_CHANNELS
&& ppmDev.pulseIndex <= PPM_IN_MAX_NUM_CHANNELS) {
/* If we see n simultaneous frames of the same
number of channels we save it as our frame size */
if (ppmDev.stableFramesSeenCount < PPM_STABLE_FRAMES_REQUIRED_COUNT) {
ppmDev.stableFramesSeenCount++;
} else {
ppmDev.numChannels = ppmDev.pulseIndex;
}
} else {
ppmDev.stableFramesSeenCount = 0;
}
/* Check if the last frame was well formed */
if (ppmDev.pulseIndex == ppmDev.numChannels && ppmDev.tracking) {
/* The last frame was well formed */
for (i = 0; i < ppmDev.numChannels; i++) {
captures[i] = ppmDev.captures[i];
}
for (i = ppmDev.numChannels; i < PPM_IN_MAX_NUM_CHANNELS; i++) {
captures[i] = PPM_RCVR_TIMEOUT;
}
ppmFrameCount++;
}
ppmDev.tracking = true;
ppmDev.numChannelsPrevFrame = ppmDev.pulseIndex;
ppmDev.pulseIndex = 0;
/* We rely on the supervisor to set captureValue to invalid
if no valid frame is found otherwise we ride over it */
} else if (ppmDev.tracking) {
/* Valid pulse duration 0.75 to 2.5 ms*/
if (ppmDev.deltaTime > PPM_IN_MIN_CHANNEL_PULSE_US
&& ppmDev.deltaTime < PPM_IN_MAX_CHANNEL_PULSE_US
&& ppmDev.pulseIndex < PPM_IN_MAX_NUM_CHANNELS) {
ppmDev.captures[ppmDev.pulseIndex] = ppmDev.deltaTime;
ppmDev.pulseIndex++;
} else {
/* Not a valid pulse duration */
ppmDev.tracking = false;
for (i = 0; i < PWM_PORTS_OR_PPM_CAPTURE_COUNT; i++) {
ppmDev.captures[i] = PPM_RCVR_TIMEOUT;
}
}
}
}
