95 lines
2.9 KiB
C++
95 lines
2.9 KiB
C++
#include <AP_HAL/AP_HAL.h>
|
|
#include "AP_BattMonitor_FuelLevel_PWM.h"
|
|
#include <GCS_MAVLink/GCS.h>
|
|
|
|
/*
|
|
"battery" monitor for liquid fuel level systems that give a PWM value indicating quantity of remaining fuel.
|
|
|
|
Output is:
|
|
|
|
- mAh remaining is fuel level in millilitres
|
|
- consumed mAh is in consumed millilitres
|
|
- fixed 1.0v voltage
|
|
*/
|
|
extern const AP_HAL::HAL& hal;
|
|
|
|
/// Constructor
|
|
AP_BattMonitor_FuelLevel_PWM::AP_BattMonitor_FuelLevel_PWM(AP_BattMonitor &mon, AP_BattMonitor::BattMonitor_State &mon_state, AP_BattMonitor_Params ¶ms) :
|
|
AP_BattMonitor_Backend(mon, mon_state, params)
|
|
{
|
|
_state.voltage = 1.0; // show a fixed voltage of 1v
|
|
|
|
// need to add check
|
|
_state.healthy = false;
|
|
}
|
|
|
|
/*
|
|
handle interrupt on an instance
|
|
*/
|
|
void AP_BattMonitor_FuelLevel_PWM::irq_handler(uint8_t pin, bool pin_state, uint32_t timestamp)
|
|
{
|
|
if (pin_state == 1) {
|
|
irq_state.last_pulse_us = timestamp;
|
|
} else if (irq_state.last_pulse_us != 0) {
|
|
irq_state.pulse_width_us = timestamp - irq_state.last_pulse_us;
|
|
irq_state.pulse_count1 ++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
read - read the "voltage" and "current"
|
|
*/
|
|
void AP_BattMonitor_FuelLevel_PWM::read()
|
|
{
|
|
int8_t pin = _params._curr_pin;
|
|
if (last_pin != pin) {
|
|
// detach from last pin
|
|
if (last_pin != -1) {
|
|
hal.gpio->detach_interrupt(last_pin);
|
|
}
|
|
// attach to new pin
|
|
last_pin = pin;
|
|
if (last_pin > 0) {
|
|
hal.gpio->pinMode(last_pin, HAL_GPIO_INPUT);
|
|
if (!hal.gpio->attach_interrupt(
|
|
last_pin,
|
|
FUNCTOR_BIND_MEMBER(&AP_BattMonitor_FuelLevel_PWM::irq_handler, void, uint8_t, bool, uint32_t),
|
|
AP_HAL::GPIO::INTERRUPT_BOTH)) {
|
|
gcs().send_text(MAV_SEVERITY_WARNING, "FuelLevelPWM: Failed to attach to pin %u", unsigned(last_pin));
|
|
}
|
|
}
|
|
}
|
|
uint32_t now_us = AP_HAL::micros();
|
|
if (pulse_count2 == irq_state.pulse_count1) {
|
|
_state.healthy = (now_us - _state.last_time_micros) < 250000U;
|
|
return;
|
|
}
|
|
uint32_t pulse_width = irq_state.pulse_width_us;
|
|
pulse_count2 = irq_state.pulse_count1;
|
|
|
|
/*
|
|
this driver assumes that CAPACITY is set to tank volume in millilitres.
|
|
*/
|
|
const uint16_t pwm_empty = 1100;
|
|
const uint16_t pwm_full = 1900;
|
|
const uint16_t pwm_buffer = 20;
|
|
|
|
|
|
// check for invalid pulse
|
|
if (pulse_width <= (pwm_empty - pwm_buffer)|| pulse_width >= (pwm_full + pwm_buffer)) {
|
|
return;
|
|
}
|
|
pulse_width = constrain_int16(pulse_width, pwm_empty, pwm_full);
|
|
float proportion_full = (pulse_width - pwm_empty) / float(pwm_full - pwm_empty);
|
|
float proportion_used = 1.0 - proportion_full;
|
|
|
|
_state.last_time_micros = now_us;
|
|
_state.healthy = true;
|
|
|
|
// map consumed_mah to consumed millilitres
|
|
_state.consumed_mah = proportion_used * _params._pack_capacity;
|
|
|
|
// map consumed_wh using fixed voltage of 1
|
|
_state.consumed_wh = _state.consumed_mah;
|
|
}
|