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#include "ms5607.hpp"
static const int32_t altitude_table[] = {
#include "altitude-pa.h"
};
#define ALT_SCALE (1 << ALT_SHIFT)
#define ALT_MASK (ALT_SCALE - 1)
void MS5607::initialize() {
sample_state = NOT_SAMPLING;
alarm_pool_init_default();
ms5607_cmd cmd;
cmd.data = RESET_COMMAND;
ms5607_write_cmd(&cmd);
sleep_ms(500);
cmd.data = 0;
cmd.fields.PROM = true;
cmd.fields.PROM2 = true;
cmd.fields.ADDR_OSR = PROM_CALIBRATION_COEFFICENT_1_ADDR;
for (uint8_t prom_addr = PROM_CALIBRATION_COEFFICENT_1_ADDR; prom_addr <= PROM_CALIBRATION_COEFFICENT_6_ADDR; prom_addr++) {
sleep_ms(100);
cmd.fields.ADDR_OSR = prom_addr;
ms5607_write_cmd(&cmd);
i2c_read_blocking(i2c, addr, buffer, 2, false);
prom[prom_addr - 1] = static_cast<uint16_t>((((uint16_t) buffer[0]) << 8) | ((uint16_t) buffer[1]));
}
}
void MS5607::ms5607_write_cmd(ms5607_cmd* cmd) {
i2c_write_blocking(i2c, addr, (uint8_t *) cmd, 1, false);
}
void MS5607::ms5607_start_sample() {
if (sample_state == NOT_SAMPLING) {
sample_state = PRESSURE_CONVERT;
ms5607_sample();
}
}
#if (USE_FREERTOS == 1)
void MS5607::ms5607_sample_handler(void* pvParameters) {
/* xMaxExpectedBlockTime is set to be a little longer than the maximum
expected time between events. */
const TickType_t xInterruptFrequency = pdMS_TO_TICKS( 1000 / (MS5607_SAMPLE_RATE_HZ * 2) );
const TickType_t xMaxExpectedBlockTime = xInterruptFrequency + pdMS_TO_TICKS( 1 );
uint32_t ulEventsToProcess;
while (1) {
/* Wait to receive a notification sent directly to this task from the
interrupt service routine. */
ulEventsToProcess = ulTaskNotifyTake( pdTRUE, xMaxExpectedBlockTime );
if( ulEventsToProcess != 0 ) {
/* To get here at least one event must have occurred. Loop here
until all the pending events have been processed */
while( ulEventsToProcess > 0 ) {
MS5607* alt = (MS5607 *) pvParameters;
taskENTER_CRITICAL();
alt->ms5607_sample();
taskEXIT_CRITICAL();
ulEventsToProcess--;
}
}
}
}
void MS5607::update_ms5607_task(void* pvParameters) {
TickType_t xLastWakeTime;
const TickType_t xFrequency = pdMS_TO_TICKS(1000 / MS5607_SAMPLE_RATE_HZ);
xLastWakeTime = xTaskGetTickCount();
while (1) {
vTaskDelayUntil(&xLastWakeTime, xFrequency);
MS5607* alt = (MS5607 *) pvParameters;
taskENTER_CRITICAL();
alt->ms5607_start_sample();
taskEXIT_CRITICAL();
}
}
#endif
int64_t MS5607::ms5607_sample_callback(alarm_id_t id, void* user_data) {
#if ( USE_FREERTOS == 1 )
BaseType_t xHigherPriorityTaskWoken;
xHigherPriorityTaskWoken = pdFALSE;
MS5607* alt = (MS5607 *) user_data;
// Defer ISR handling to separate handler within FreeRTOS context
vTaskNotifyGiveFromISR(alt->sample_handler_task_handle, &xHigherPriorityTaskWoken );
portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
#else
MS5607* alt = (MS5607 *) user_data;
alt->ms5607_sample();
#endif
return 0;
}
void MS5607::ms5607_sample() {
ms5607_cmd cmd = {.data = 0};
switch (sample_state) {
case NOT_SAMPLING:
break;
case PRESSURE_CONVERT: {
cmd.fields.CONVERT = 1;
cmd.fields.TYPE = TYPE_UNCOMPENSATED_PRESSURE;
cmd.fields.ADDR_OSR = OSR_CONVERT_256;
ms5607_write_cmd(&cmd);
add_alarm_in_us(OSR_256_CONVERSION_TIME_US, MS5607::ms5607_sample_callback, (void *) this, true);
sample_state = TEMPERATURE_CONVERT;
break;
};
case TEMPERATURE_CONVERT: {
cmd.data = ADC_READ_COMMAND;
ms5607_write_cmd(&cmd);
i2c_read_blocking(i2c, addr, buffer, 3, false);
uncompensated_pressure = (((uint32_t) buffer[0]) << 16) | (((uint32_t) buffer[1]) << 8) | ((uint32_t) buffer[2]);
cmd.fields.CONVERT = 1;
cmd.fields.TYPE = TYPE_UNCOMPENSATED_TEMPERATURE;
cmd.fields.ADDR_OSR = OSR_CONVERT_256;
ms5607_write_cmd(&cmd);
add_alarm_in_us(OSR_256_CONVERSION_TIME_US, MS5607::ms5607_sample_callback, (void *) this, true);
sample_state = COMPENSATE;
break;
};
case COMPENSATE: {
cmd.data = ADC_READ_COMMAND;
ms5607_write_cmd(&cmd);
i2c_read_blocking(i2c, addr, buffer, 3, false);
uncompensated_temperature = (((uint32_t) buffer[0]) << 16) | (((uint32_t) buffer[1]) << 8) | ((uint32_t) buffer[2]);
ms5607_compensate();
altitude = pressure_to_altitude(pressure);
sample_state = NOT_SAMPLING;
if (threshold_callback != NULL) {
if (positive_crossing) {
if (altitude >= threshold_altitude) {
add_alarm_in_ms(1, threshold_callback, NULL, true);
}
} else {
if (altitude <= threshold_altitude) {
add_alarm_in_ms(1, threshold_callback, NULL, true);
}
}
}
break;
};
};
}
void MS5607::ms5607_compensate() {
int32_t dT = uncompensated_temperature - (((uint32_t) prom[4]) << 8);
temperature = 2000 + ( ( ( (int64_t) dT) * ( (int64_t) prom[5]) ) >> 23);
int64_t OFF = ( ( (int64_t) prom[1]) << 17) + ( ( ((int64_t) prom[3]) * ( (int64_t) dT)) >> 6);
int64_t SENS = ( ( (int64_t) prom[0]) << 16) + (( ( (int64_t) prom[2]) * ((int64_t) dT)) >> 7);
pressure = (int32_t) ((((((int64_t) uncompensated_pressure) * SENS) >> 21) - OFF) >> 15);
}
int32_t MS5607::pressure_to_altitude(int32_t pressure) {
uint16_t o;
int16_t part;
int32_t low, high;
if (pressure < 0) {
pressure = 0;
}
if (pressure > 120000) {
pressure = 120000;
}
o = (uint16_t) (pressure >> ALT_SHIFT);
part = pressure & ALT_MASK;
low = (int32_t) altitude_table[o] * (ALT_SCALE - part);
high = (int32_t) altitude_table[o + 1] * part;
return ((low + high + (ALT_SCALE >> 1)) >> ALT_SHIFT);
}
void MS5607::set_threshold_altitude(int32_t threshold_altitude, alarm_callback_t callback) {
this->threshold_altitude = threshold_altitude;
positive_crossing = (threshold_altitude > altitude);
threshold_callback = callback;
}
void MS5607::clear_threshold_altitude() {
this->threshold_callback = NULL;
}
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