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CC3D - Support PPM input on IN_S1.

Browse source 
This required timer overflow events to be used in the calculation of PPM
channel data.

CC3D tested, other targets may be unstable as a result. Needs further
testing.
This commit is contained in:
Dominic Clifton 2014-07-22 21:29:00 +01:00
parent 440e942af4
commit a5ec1355d4
6 changed files with 69 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

32
src/main/drivers/pwm_rx.c
View file

@ -79,18 +79,36 @@ void resetPPMDataReceivedState(void)
#define MIN_CHANNELS_BEFORE_PPM_FRAME_CONSIDERED_VALID 4
static void ppmCallback(uint8_t port, captureCompare_t capture)
uint32_t largeCounter = 0;
static void ppmOverflowCallback(uint8_t port, captureCompare_t capture)
{
uint16_t diff; // See PPM_TIMER_PERIOD
static captureCompare_t now;
static captureCompare_t last = 0;
largeCounter += capture;
}
static void ppmEdgeCallback(uint8_t port, captureCompare_t capture)
{
uint32_t diff; // See PPM_TIMER_PERIOD
static uint32_t now = 0;
static uint32_t last = 0;
static uint8_t chan = 0;
last = now;
now = capture;
now += largeCounter;
diff = now - last;
#if 0
static uint32_t diffs[20];
static uint8_t diffIndex = 0;
diffIndex = (diffIndex + 1) % 20;
diffs[diffIndex] = diff;
#endif
if (diff > 2700) { // Per http://www.rcgroups.com/forums/showpost.php?p=21996147&postcount=3960 "So, if you use 2.5ms or higher as being the reset for the PPM stream start, you will be fine. I use 2.7ms just to be safe."
if (chan >= MIN_CHANNELS_BEFORE_PPM_FRAME_CONSIDERED_VALID) {
ppmFrameCount++;
@ -105,7 +123,7 @@ static void ppmCallback(uint8_t port, captureCompare_t capture)
}
static void pwmCallback(uint8_t port, captureCompare_t capture)
static void pwmEdgeCallback(uint8_t port, captureCompare_t capture)
{
pwmInputPort_t *pwmInputPort = &pwmInputPorts[port];
const timerHardware_t *timerHardware = pwmInputPort->timerHardware;
@ -167,7 +185,7 @@ void pwmInConfig(uint8_t timerIndex, uint8_t channel)
pwmICConfig(timerHardwarePtr->tim, timerHardwarePtr->channel, TIM_ICPolarity_Rising);
timerConfigure(timerHardwarePtr, PWM_TIMER_PERIOD, PWM_TIMER_MHZ);
configureTimerCaptureCompareInterrupt(timerHardwarePtr, channel, pwmCallback);
configureTimerCaptureCompareInterrupt(timerHardwarePtr, channel, pwmEdgeCallback, NULL);
}
#define UNUSED_PPM_TIMER_REFERENCE 0
@ -186,7 +204,7 @@ void ppmInConfig(uint8_t timerIndex)
pwmICConfig(timerHardwarePtr->tim, timerHardwarePtr->channel, TIM_ICPolarity_Rising);
timerConfigure(timerHardwarePtr, PPM_TIMER_PERIOD, PWM_TIMER_MHZ);
configureTimerCaptureCompareInterrupt(timerHardwarePtr, UNUSED_PPM_TIMER_REFERENCE, ppmCallback);
configureTimerCaptureCompareInterrupt(timerHardwarePtr, UNUSED_PPM_TIMER_REFERENCE, ppmEdgeCallback, ppmOverflowCallback);
}
uint16_t pwmRead(uint8_t channel)