330 lines
10 KiB
C
330 lines
10 KiB
C
/*
|
|
* This file is part of Cleanflight.
|
|
*
|
|
* Cleanflight is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* Cleanflight is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Cleanflight. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <stdbool.h>
|
|
#include <stdint.h>
|
|
|
|
#include <stdlib.h>
|
|
|
|
#include "platform.h"
|
|
#include "build_config.h"
|
|
|
|
#include "gpio.h"
|
|
#include "timer.h"
|
|
|
|
#include "pwm_mapping.h"
|
|
|
|
#include "pwm_rx.h"
|
|
|
|
#define PPM_CAPTURE_COUNT 12
|
|
#define PWM_INPUT_PORT_COUNT 8
|
|
|
|
#if PPM_CAPTURE_COUNT > MAX_PWM_INPUT_PORTS
|
|
#define PWM_PORTS_OR_PPM_CAPTURE_COUNT PPM_CAPTURE_COUNT
|
|
#else
|
|
#define PWM_PORTS_OR_PPM_CAPTURE_COUNT PWM_INPUT_PORT_COUNT
|
|
#endif
|
|
|
|
#define INPUT_FILTER_TO_HELP_WITH_NOISE_FROM_OPENLRS_TELEMETRY_RX 0x03
|
|
|
|
static inputFilteringMode_e inputFilteringMode;
|
|
|
|
void pwmICConfig(TIM_TypeDef *tim, uint8_t channel, uint16_t polarity);
|
|
|
|
typedef enum {
|
|
INPUT_MODE_PPM,
|
|
INPUT_MODE_PWM,
|
|
} pwmInputMode_t;
|
|
|
|
typedef struct {
|
|
pwmInputMode_t mode;
|
|
uint8_t channel; // only used for pwm, ignored by ppm
|
|
|
|
uint8_t state;
|
|
captureCompare_t rise;
|
|
captureCompare_t fall;
|
|
captureCompare_t capture;
|
|
|
|
uint8_t missedEvents;
|
|
|
|
const timerHardware_t *timerHardware;
|
|
} pwmInputPort_t;
|
|
|
|
static pwmInputPort_t pwmInputPorts[PWM_INPUT_PORT_COUNT];
|
|
|
|
static uint16_t captures[PWM_PORTS_OR_PPM_CAPTURE_COUNT];
|
|
|
|
#define PPM_TIMER_PERIOD 0xFFFF
|
|
#define PWM_TIMER_PERIOD 0xFFFF
|
|
|
|
static uint8_t ppmFrameCount = 0;
|
|
static uint8_t lastPPMFrameCount = 0;
|
|
|
|
typedef struct ppmDevice {
|
|
uint8_t pulseIndex;
|
|
uint32_t previousTime;
|
|
uint32_t currentTime;
|
|
uint32_t deltaTime;
|
|
uint32_t captures[PWM_PORTS_OR_PPM_CAPTURE_COUNT];
|
|
uint32_t largeCounter;
|
|
int8_t numChannels;
|
|
int8_t numChannelsPrevFrame;
|
|
uint8_t stableFramesSeenCount;
|
|
|
|
bool tracking;
|
|
} ppmDevice_t;
|
|
|
|
ppmDevice_t ppmDev;
|
|
|
|
|
|
#define PPM_IN_MIN_SYNC_PULSE_US 2700 // microseconds
|
|
#define PPM_IN_MIN_CHANNEL_PULSE_US 750 // microseconds
|
|
#define PPM_IN_MAX_CHANNEL_PULSE_US 2250 // microseconds
|
|
#define PPM_STABLE_FRAMES_REQUIRED_COUNT 25
|
|
#define PPM_IN_MIN_NUM_CHANNELS 4
|
|
#define PPM_IN_MAX_NUM_CHANNELS PWM_PORTS_OR_PPM_CAPTURE_COUNT
|
|
#define PPM_RCVR_TIMEOUT 0
|
|
|
|
|
|
bool isPPMDataBeingReceived(void)
|
|
{
|
|
return (ppmFrameCount != lastPPMFrameCount);
|
|
}
|
|
|
|
void resetPPMDataReceivedState(void)
|
|
{
|
|
lastPPMFrameCount = ppmFrameCount;
|
|
}
|
|
|
|
#define MIN_CHANNELS_BEFORE_PPM_FRAME_CONSIDERED_VALID 4
|
|
|
|
void pwmRxInit(inputFilteringMode_e initialInputFilteringMode)
|
|
{
|
|
inputFilteringMode = initialInputFilteringMode;
|
|
}
|
|
|
|
static void ppmInit(void)
|
|
{
|
|
ppmDev.pulseIndex = 0;
|
|
ppmDev.previousTime = 0;
|
|
ppmDev.currentTime = 0;
|
|
ppmDev.deltaTime = 0;
|
|
ppmDev.largeCounter = 0;
|
|
ppmDev.numChannels = -1;
|
|
ppmDev.numChannelsPrevFrame = -1;
|
|
ppmDev.stableFramesSeenCount = 0;
|
|
ppmDev.tracking = false;
|
|
}
|
|
|
|
static void ppmOverflowCallback(uint8_t port, captureCompare_t capture)
|
|
{
|
|
UNUSED(port);
|
|
ppmDev.largeCounter += capture;
|
|
}
|
|
|
|
static void ppmEdgeCallback(uint8_t port, captureCompare_t capture)
|
|
{
|
|
UNUSED(port);
|
|
int32_t i;
|
|
|
|
/* Shift the last measurement out */
|
|
ppmDev.previousTime = ppmDev.currentTime;
|
|
|
|
/* Grab the new count */
|
|
ppmDev.currentTime = capture;
|
|
|
|
/* Convert to 32-bit timer result */
|
|
ppmDev.currentTime += ppmDev.largeCounter;
|
|
|
|
/* Capture computation */
|
|
ppmDev.deltaTime = ppmDev.currentTime - ppmDev.previousTime;
|
|
|
|
ppmDev.previousTime = ppmDev.currentTime;
|
|
|
|
#if 0
|
|
static uint32_t deltaTimes[20];
|
|
static uint8_t deltaIndex = 0;
|
|
|
|
deltaIndex = (deltaIndex + 1) % 20;
|
|
deltaTimes[deltaIndex] = ppmDev.deltaTime;
|
|
#endif
|
|
|
|
/* 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;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static uint8_t pwmChannelsReceived = 0;
|
|
|
|
#define MAX_MISSED_PWM_EVENTS 10
|
|
#define MAX_MISSED_PWM_EVENT_COUNTER (MAX_MISSED_PWM_EVENTS * PWM_TIMER_PERIOD)
|
|
|
|
extern uint16_t debug[4];
|
|
static void pwmOverflowCallback(uint8_t port, captureCompare_t capture)
|
|
{
|
|
UNUSED(capture);
|
|
pwmInputPort_t *pwmInputPort = &pwmInputPorts[port];
|
|
|
|
if (++pwmInputPort->missedEvents > MAX_MISSED_PWM_EVENTS) {
|
|
if (pwmInputPort->state == 0) {
|
|
captures[pwmInputPort->channel] = PPM_RCVR_TIMEOUT;
|
|
}
|
|
pwmInputPort->missedEvents = 0;
|
|
}
|
|
}
|
|
|
|
static void pwmEdgeCallback(uint8_t port, captureCompare_t capture)
|
|
{
|
|
pwmInputPort_t *pwmInputPort = &pwmInputPorts[port];
|
|
const timerHardware_t *timerHardwarePtr = pwmInputPort->timerHardware;
|
|
|
|
if (pwmInputPort->state == 0) {
|
|
pwmInputPort->rise = capture;
|
|
pwmInputPort->state = 1;
|
|
pwmICConfig(timerHardwarePtr->tim, timerHardwarePtr->channel, TIM_ICPolarity_Falling);
|
|
} else {
|
|
pwmInputPort->fall = capture;
|
|
|
|
// compute and store capture
|
|
pwmInputPort->capture = pwmInputPort->fall - pwmInputPort->rise;
|
|
captures[pwmInputPort->channel] = pwmInputPort->capture;
|
|
|
|
// switch state
|
|
pwmInputPort->state = 0;
|
|
pwmICConfig(timerHardwarePtr->tim, timerHardwarePtr->channel, TIM_ICPolarity_Rising);
|
|
pwmChannelsReceived |= (1 << pwmInputPort->channel);
|
|
pwmInputPort->missedEvents = 0;
|
|
}
|
|
}
|
|
|
|
static void pwmGPIOConfig(GPIO_TypeDef *gpio, uint32_t pin, GPIO_Mode mode)
|
|
{
|
|
gpio_config_t cfg;
|
|
|
|
cfg.pin = pin;
|
|
cfg.mode = mode;
|
|
cfg.speed = Speed_2MHz;
|
|
gpioInit(gpio, &cfg);
|
|
}
|
|
|
|
void pwmICConfig(TIM_TypeDef *tim, uint8_t channel, uint16_t polarity)
|
|
{
|
|
TIM_ICInitTypeDef TIM_ICInitStructure;
|
|
|
|
TIM_ICStructInit(&TIM_ICInitStructure);
|
|
TIM_ICInitStructure.TIM_Channel = channel;
|
|
TIM_ICInitStructure.TIM_ICPolarity = polarity;
|
|
TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
|
|
TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
|
|
|
|
if (inputFilteringMode == INPUT_FILTERING_ENABLED) {
|
|
TIM_ICInitStructure.TIM_ICFilter = INPUT_FILTER_TO_HELP_WITH_NOISE_FROM_OPENLRS_TELEMETRY_RX;
|
|
} else {
|
|
TIM_ICInitStructure.TIM_ICFilter = 0x00;
|
|
}
|
|
|
|
TIM_ICInit(tim, &TIM_ICInitStructure);
|
|
}
|
|
|
|
void pwmInConfig(const timerHardware_t *timerHardwarePtr, uint8_t channel)
|
|
{
|
|
pwmInputPort_t *p = &pwmInputPorts[channel];
|
|
|
|
p->state = 0;
|
|
p->missedEvents = 0;
|
|
p->channel = channel;
|
|
p->mode = INPUT_MODE_PWM;
|
|
p->timerHardware = timerHardwarePtr;
|
|
|
|
pwmGPIOConfig(timerHardwarePtr->gpio, timerHardwarePtr->pin, timerHardwarePtr->gpioInputMode);
|
|
pwmICConfig(timerHardwarePtr->tim, timerHardwarePtr->channel, TIM_ICPolarity_Rising);
|
|
|
|
timerConfigure(timerHardwarePtr, PWM_TIMER_PERIOD, PWM_TIMER_MHZ);
|
|
configureTimerCaptureCompareInterrupt(timerHardwarePtr, channel, pwmEdgeCallback, pwmOverflowCallback);
|
|
}
|
|
|
|
#define UNUSED_PPM_TIMER_REFERENCE 0
|
|
#define FIRST_PWM_PORT 0
|
|
|
|
void ppmInConfig(const timerHardware_t *timerHardwarePtr)
|
|
{
|
|
ppmInit();
|
|
|
|
pwmInputPort_t *p = &pwmInputPorts[FIRST_PWM_PORT];
|
|
|
|
p->mode = INPUT_MODE_PPM;
|
|
p->timerHardware = timerHardwarePtr;
|
|
|
|
pwmGPIOConfig(timerHardwarePtr->gpio, timerHardwarePtr->pin, timerHardwarePtr->gpioInputMode);
|
|
pwmICConfig(timerHardwarePtr->tim, timerHardwarePtr->channel, TIM_ICPolarity_Rising);
|
|
|
|
timerConfigure(timerHardwarePtr, PPM_TIMER_PERIOD, PWM_TIMER_MHZ);
|
|
configureTimerCaptureCompareInterrupt(timerHardwarePtr, UNUSED_PPM_TIMER_REFERENCE, ppmEdgeCallback, ppmOverflowCallback);
|
|
}
|
|
|
|
uint16_t pwmRead(uint8_t channel)
|
|
{
|
|
return captures[channel];
|
|
}
|
|
|