move thermistor calculation to watch utilities

This commit is contained in:
Joey Castillo
2021-11-22 17:31:51 -05:00
parent fb8f4584a5
commit 0ca729eaba
4 changed files with 66 additions and 65 deletions

View File

@@ -22,6 +22,7 @@
* SOFTWARE.
*/
#include <math.h>
#include "watch_utility.h"
const char * watch_utility_get_weekday(watch_date_time date_time) {
@@ -33,3 +34,23 @@ const char * watch_utility_get_weekday(watch_date_time date_time) {
}
return weekdays[(date_time.unit.day + 13 * (date_time.unit.month + 1) / 5 + date_time.unit.year + date_time.unit.year / 4 + 525) % 7];
}
float watch_utility_thermistor_temperature(uint16_t value, bool highside, float b_coefficient, float nominal_temperature, float nominal_resistance, float series_resistance) {
float reading = (float)value;
if (highside) {
reading = (1023.0 * series_resistance) / (reading / 64.0);
reading -= series_resistance;
} else {
reading = series_resistance / (65535.0 / value - 1.0);
}
reading = reading / nominal_resistance;
reading = log(reading);
reading /= b_coefficient;
reading += 1.0 / (nominal_temperature + 273.15);
reading = 1.0 / reading;
reading -= 273.15;
return reading;
}