mirror of https://github.com/ArduPilot/ardupilot
252 lines
6.6 KiB
C++
252 lines
6.6 KiB
C++
#include "RCOutput_PCA9685.h"
|
|
|
|
#include <cmath>
|
|
#include <dirent.h>
|
|
#include <fcntl.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
#include <utility>
|
|
|
|
#include <AP_HAL/AP_HAL.h>
|
|
|
|
#include "GPIO.h"
|
|
|
|
#define PCA9685_RA_MODE1 0x00
|
|
#define PCA9685_RA_MODE2 0x01
|
|
#define PCA9685_RA_LED0_ON_L 0x06
|
|
#define PCA9685_RA_LED0_ON_H 0x07
|
|
#define PCA9685_RA_LED0_OFF_L 0x08
|
|
#define PCA9685_RA_LED0_OFF_H 0x09
|
|
#define PCA9685_RA_ALL_LED_ON_L 0xFA
|
|
#define PCA9685_RA_ALL_LED_ON_H 0xFB
|
|
#define PCA9685_RA_ALL_LED_OFF_L 0xFC
|
|
#define PCA9685_RA_ALL_LED_OFF_H 0xFD
|
|
#define PCA9685_RA_PRE_SCALE 0xFE
|
|
|
|
#define PCA9685_MODE1_RESTART_BIT (1 << 7)
|
|
#define PCA9685_MODE1_EXTCLK_BIT (1 << 6)
|
|
#define PCA9685_MODE1_AI_BIT (1 << 5)
|
|
#define PCA9685_MODE1_SLEEP_BIT (1 << 4)
|
|
#define PCA9685_MODE1_SUB1_BIT (1 << 3)
|
|
#define PCA9685_MODE1_SUB2_BIT (1 << 2)
|
|
#define PCA9685_MODE1_SUB3_BIT (1 << 1)
|
|
#define PCA9685_MODE1_ALLCALL_BIT (1 << 0)
|
|
#define PCA9685_ALL_LED_OFF_H_SHUT (1 << 4)
|
|
#define PCA9685_MODE2_INVRT_BIT (1 << 4)
|
|
#define PCA9685_MODE2_OCH_BIT (1 << 3)
|
|
#define PCA9685_MODE2_OUTDRV_BIT (1 << 2)
|
|
#define PCA9685_MODE2_OUTNE1_BIT (1 << 1)
|
|
#define PCA9685_MODE2_OUTNE0_BIT (1 << 0)
|
|
|
|
/*
|
|
* Drift for internal oscillator
|
|
* see: https://github.com/ArduPilot/ardupilot/commit/50459bdca0b5a1adf95
|
|
* and https://github.com/adafruit/Adafruit-PWM-Servo-Driver-Library/issues/11
|
|
*/
|
|
#define PCA9685_INTERNAL_CLOCK (1.04f * 25000000.f)
|
|
#define PCA9685_EXTERNAL_CLOCK 24576000.f
|
|
|
|
using namespace Linux;
|
|
|
|
#define PWM_CHAN_COUNT 16
|
|
|
|
static const AP_HAL::HAL& hal = AP_HAL::get_HAL();
|
|
|
|
RCOutput_PCA9685::RCOutput_PCA9685(AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev,
|
|
bool external_clock,
|
|
uint8_t channel_offset,
|
|
int16_t oe_pin_number) :
|
|
_dev(std::move(dev)),
|
|
_enable_pin(nullptr),
|
|
_frequency(50),
|
|
_pulses_buffer(new uint16_t[PWM_CHAN_COUNT - channel_offset]),
|
|
_external_clock(external_clock),
|
|
_channel_offset(channel_offset),
|
|
_oe_pin_number(oe_pin_number)
|
|
{
|
|
if (_external_clock)
|
|
_osc_clock = PCA9685_EXTERNAL_CLOCK;
|
|
else
|
|
_osc_clock = PCA9685_INTERNAL_CLOCK;
|
|
}
|
|
|
|
RCOutput_PCA9685::~RCOutput_PCA9685()
|
|
{
|
|
delete [] _pulses_buffer;
|
|
}
|
|
|
|
void RCOutput_PCA9685::init()
|
|
{
|
|
reset_all_channels();
|
|
|
|
/* Set the initial frequency */
|
|
set_freq(0, 50);
|
|
|
|
/* Enable PCA9685 PWM */
|
|
if (_oe_pin_number != -1) {
|
|
_enable_pin = hal.gpio->channel(_oe_pin_number);
|
|
_enable_pin->mode(HAL_GPIO_OUTPUT);
|
|
_enable_pin->write(0);
|
|
}
|
|
}
|
|
|
|
void RCOutput_PCA9685::reset_all_channels()
|
|
{
|
|
if (!_dev->get_semaphore()->take(10)) {
|
|
return;
|
|
}
|
|
|
|
uint8_t data[] = {PCA9685_RA_ALL_LED_ON_L, 0, 0, 0, 0};
|
|
_dev->transfer(data, sizeof(data), nullptr, 0);
|
|
|
|
/* Wait for the last pulse to end */
|
|
hal.scheduler->delay(2);
|
|
|
|
_dev->get_semaphore()->give();
|
|
}
|
|
|
|
void RCOutput_PCA9685::set_freq(uint32_t chmask, uint16_t freq_hz)
|
|
{
|
|
|
|
/* Correctly finish last pulses */
|
|
for (int i = 0; i < (PWM_CHAN_COUNT - _channel_offset); i++) {
|
|
write(i, _pulses_buffer[i]);
|
|
}
|
|
|
|
if (!_dev->get_semaphore()->take(10)) {
|
|
return;
|
|
}
|
|
|
|
/* Shutdown before sleeping.
|
|
* see p.14 of PCA9685 product datasheet
|
|
*/
|
|
_dev->write_register(PCA9685_RA_ALL_LED_OFF_H, PCA9685_ALL_LED_OFF_H_SHUT);
|
|
|
|
/* Put PCA9685 to sleep (required to write prescaler) */
|
|
_dev->write_register(PCA9685_RA_MODE1, PCA9685_MODE1_SLEEP_BIT);
|
|
|
|
/* Calculate prescale and save frequency using this value: it may be
|
|
* different from @freq_hz due to rounding/ceiling. We use ceil() rather
|
|
* than round() so the resulting frequency is never greater than @freq_hz
|
|
*/
|
|
uint8_t prescale = ceil(_osc_clock / (4096 * freq_hz)) - 1;
|
|
_frequency = _osc_clock / (4096 * (prescale + 1));
|
|
|
|
/* Write prescale value to match frequency */
|
|
_dev->write_register(PCA9685_RA_PRE_SCALE, prescale);
|
|
|
|
if (_external_clock) {
|
|
/* Enable external clocking */
|
|
_dev->write_register(PCA9685_RA_MODE1,
|
|
PCA9685_MODE1_SLEEP_BIT | PCA9685_MODE1_EXTCLK_BIT);
|
|
}
|
|
|
|
/* Restart the device to apply new settings and enable auto-incremented write */
|
|
_dev->write_register(PCA9685_RA_MODE1,
|
|
PCA9685_MODE1_RESTART_BIT | PCA9685_MODE1_AI_BIT);
|
|
|
|
_dev->get_semaphore()->give();
|
|
}
|
|
|
|
uint16_t RCOutput_PCA9685::get_freq(uint8_t ch)
|
|
{
|
|
return _frequency;
|
|
}
|
|
|
|
void RCOutput_PCA9685::enable_ch(uint8_t ch)
|
|
{
|
|
|
|
}
|
|
|
|
void RCOutput_PCA9685::disable_ch(uint8_t ch)
|
|
{
|
|
write(ch, 0);
|
|
}
|
|
|
|
void RCOutput_PCA9685::write(uint8_t ch, uint16_t period_us)
|
|
{
|
|
if (ch >= (PWM_CHAN_COUNT - _channel_offset)) {
|
|
return;
|
|
}
|
|
|
|
_pulses_buffer[ch] = period_us;
|
|
_pending_write_mask |= (1U << ch);
|
|
|
|
if (!_corking) {
|
|
_corking = true;
|
|
push();
|
|
}
|
|
}
|
|
|
|
void RCOutput_PCA9685::cork()
|
|
{
|
|
_corking = true;
|
|
}
|
|
|
|
void RCOutput_PCA9685::push()
|
|
{
|
|
if (!_corking) {
|
|
return;
|
|
}
|
|
_corking = false;
|
|
|
|
if (_pending_write_mask == 0)
|
|
return;
|
|
|
|
// Calculate the number of channels for this transfer.
|
|
uint8_t max_ch = (sizeof(unsigned) * 8) - __builtin_clz(_pending_write_mask);
|
|
uint8_t min_ch = __builtin_ctz(_pending_write_mask);
|
|
|
|
/*
|
|
* scratch buffer size is always for all the channels, but we write only
|
|
* from min_ch to max_ch
|
|
*/
|
|
struct PACKED pwm_values {
|
|
uint8_t reg;
|
|
uint8_t data[PWM_CHAN_COUNT * 4];
|
|
} pwm_values;
|
|
|
|
for (unsigned ch = min_ch; ch < max_ch; ch++) {
|
|
uint16_t period_us = _pulses_buffer[ch];
|
|
uint16_t length = 0;
|
|
|
|
if (period_us) {
|
|
length = round((period_us * 4096) / (1000000.f / _frequency)) - 1;
|
|
}
|
|
|
|
uint8_t *d = &pwm_values.data[(ch - min_ch) * 4];
|
|
*d++ = 0;
|
|
*d++ = 0;
|
|
*d++ = length & 0xFF;
|
|
*d++ = length >> 8;
|
|
}
|
|
|
|
if (!_dev->get_semaphore()->take_nonblocking()) {
|
|
return;
|
|
}
|
|
|
|
pwm_values.reg = PCA9685_RA_LED0_ON_L + 4 * (_channel_offset + min_ch);
|
|
/* reg + all the channels we are going to write */
|
|
size_t payload_size = 1 + (max_ch - min_ch) * 4;
|
|
|
|
_dev->transfer((uint8_t *)&pwm_values, payload_size, nullptr, 0);
|
|
_dev->get_semaphore()->give();
|
|
_pending_write_mask = 0;
|
|
}
|
|
|
|
uint16_t RCOutput_PCA9685::read(uint8_t ch)
|
|
{
|
|
return _pulses_buffer[ch];
|
|
}
|
|
|
|
void RCOutput_PCA9685::read(uint16_t* period_us, uint8_t len)
|
|
{
|
|
for (int i = 0; i < len; i++) {
|
|
period_us[i] = read(0 + i);
|
|
}
|
|
}
|