/*
This program 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.
This program 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 this program. If not, see .
*/
/*
driver for PX4Flow optical flow sensor
*/
#include
#include "AP_OpticalFlow_PX4Flow.h"
#include
#include
#include
#include
#include "OpticalFlow.h"
#include
extern const AP_HAL::HAL& hal;
#define PX4FLOW_BASE_I2C_ADDR 0x42
#define PX4FLOW_INIT_RETRIES 10 // attempt to initialise the sensor up to 10 times at startup
// constructor
AP_OpticalFlow_PX4Flow::AP_OpticalFlow_PX4Flow(OpticalFlow &_frontend) :
OpticalFlow_backend(_frontend)
{
}
// detect the device
AP_OpticalFlow_PX4Flow *AP_OpticalFlow_PX4Flow::detect(OpticalFlow &_frontend)
{
AP_OpticalFlow_PX4Flow *sensor = new AP_OpticalFlow_PX4Flow(_frontend);
if (!sensor) {
return nullptr;
}
if (!sensor->setup_sensor()) {
delete sensor;
return nullptr;
}
return sensor;
}
/*
look for the sensor on different buses
*/
bool AP_OpticalFlow_PX4Flow::scan_buses(void)
{
bool success = false;
uint8_t retry_attempt = 0;
while (!success && retry_attempt < PX4FLOW_INIT_RETRIES) {
for (uint8_t bus = 0; bus < 3; bus++) {
#ifdef HAL_OPTFLOW_PX4FLOW_I2C_BUS
// only one bus from HAL
if (bus != HAL_OPTFLOW_PX4FLOW_I2C_BUS) {
continue;
}
#endif
AP_HAL::OwnPtr tdev = hal.i2c_mgr->get_device(bus, PX4FLOW_BASE_I2C_ADDR + get_address());
if (!tdev) {
continue;
}
WITH_SEMAPHORE(tdev->get_semaphore());
struct i2c_integral_frame frame;
success = tdev->read_registers(REG_INTEGRAL_FRAME, (uint8_t *)&frame, sizeof(frame));
if (success) {
printf("Found PX4Flow on bus %u\n", bus);
dev = std::move(tdev);
break;
}
}
retry_attempt++;
if (!success) {
hal.scheduler->delay(10);
}
}
return success;
}
// setup the device
bool AP_OpticalFlow_PX4Flow::setup_sensor(void)
{
if (!scan_buses()) {
return false;
}
// read at 10Hz
dev->register_periodic_callback(100000, FUNCTOR_BIND_MEMBER(&AP_OpticalFlow_PX4Flow::timer, void));
return true;
}
// update - read latest values from sensor and fill in x,y and totals.
void AP_OpticalFlow_PX4Flow::update(void)
{
}
// timer to read sensor
void AP_OpticalFlow_PX4Flow::timer(void)
{
struct i2c_integral_frame frame;
if (!dev->read_registers(REG_INTEGRAL_FRAME, (uint8_t *)&frame, sizeof(frame))) {
return;
}
struct OpticalFlow::OpticalFlow_state state {};
state.device_id = get_address();
if (frame.integration_timespan > 0) {
const Vector2f flowScaler = _flowScaler();
float flowScaleFactorX = 1.0f + 0.001f * flowScaler.x;
float flowScaleFactorY = 1.0f + 0.001f * flowScaler.y;
float integralToRate = 1.0e6 / frame.integration_timespan;
state.surface_quality = frame.qual;
state.flowRate = Vector2f(frame.pixel_flow_x_integral * flowScaleFactorX,
frame.pixel_flow_y_integral * flowScaleFactorY) * 1.0e-4 * integralToRate;
state.bodyRate = Vector2f(frame.gyro_x_rate_integral, frame.gyro_y_rate_integral) * 1.0e-4 * integralToRate;
_applyYaw(state.flowRate);
_applyYaw(state.bodyRate);
}
_update_frontend(state);
}