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#include "thermistor_driver.h"
#include "watch.h"
#include "watch_utility.h"
void thermistor_driver_enable(void) {
// Enable the ADC peripheral, which we'll use to read the thermistor value.
watch_enable_adc();
// Enable analog circuitry on the sense pin, which is tied to the thermistor resistor divider.
watch_enable_analog_input(THERMISTOR_SENSE_PIN);
// Enable digital output on the enable pin, which is the power to the thermistor circuit.
watch_enable_digital_output(THERMISTOR_ENABLE_PIN);
// and make sure it's off.
watch_set_pin_level(THERMISTOR_ENABLE_PIN, !THERMISTOR_ENABLE_VALUE);
}
void thermistor_driver_disable(void) {
// Disable the ADC peripheral.
watch_disable_adc();
// Disable analog circuitry on the sense pin to save power.
watch_disable_analog_input(THERMISTOR_SENSE_PIN);
// Disable the enable pin's output circuitry.
watch_disable_digital_output(THERMISTOR_ENABLE_PIN);
}
float thermistor_driver_get_temperature(void) {
// set the enable pin to the level that powers the thermistor circuit.
watch_set_pin_level(THERMISTOR_ENABLE_PIN, THERMISTOR_ENABLE_VALUE);
// get the sense pin level
uint16_t value = watch_get_analog_pin_level(THERMISTOR_SENSE_PIN);
// and then set the enable pin to the opposite value to power down the thermistor circuit.
watch_set_pin_level(THERMISTOR_ENABLE_PIN, !THERMISTOR_ENABLE_VALUE);
return watch_utility_thermistor_temperature(value, THERMISTOR_HIGH_SIDE, THERMISTOR_B_COEFFICIENT, THERMISTOR_NOMINAL_TEMPERATURE, THERMISTOR_NOMINAL_RESISTANCE, THERMISTOR_SERIES_RESISTANCE);
}
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