ardupilot/libraries/AP_RangeFinder/AP_RangeFinder_HC_SR04.h

44 lines
1.2 KiB
C++

#pragma once
#include "AP_RangeFinder.h"
#include "AP_RangeFinder_Backend.h"
#include "AP_RangeFinder_Params.h"
class AP_RangeFinder_HC_SR04 : public AP_RangeFinder_Backend
{
public:
// constructor
AP_RangeFinder_HC_SR04(RangeFinder::RangeFinder_State &_state, AP_RangeFinder_Params &_params);
// static detection function
static bool detect(AP_RangeFinder_Params &_params);
// update state
void update(void) override;
protected:
MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
return MAV_DISTANCE_SENSOR_ULTRASOUND;
}
private:
void check_pins();
void check_echo_pin();
void check_trigger_pin();
void irq_handler(uint8_t pin, bool pin_high, uint32_t timestamp_us);
int8_t echo_pin;
int8_t trigger_pin;
uint32_t last_reading_ms; // system time of last read (used for health reporting)
uint32_t last_distance_cm; // last distance reported (used to prevent glitches in measurement)
uint8_t glitch_count; // glitch counter
// follow are modified by the IRQ handler:
uint32_t pulse_start_us; // system time of start of timing pulse
uint32_t irq_value_us; // last calculated pwm value (irq copy)
uint32_t last_ping_ms;
};