X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2Fkernel%2Fao_motor_flight.c;h=6fa68831ea8b9350fcdc84130a33194051708ebd;hb=e4ce0ce186b68497cfb14a400410fdd38aa93abc;hp=f47f59b393eb0f5adb0d545ceb1e564e5b8f29b8;hpb=28e4cb24e0f0ee5abf66c5a0466edfd0e31f4df0;p=fw%2Faltos diff --git a/src/kernel/ao_motor_flight.c b/src/kernel/ao_motor_flight.c index f47f59b3..6fa68831 100644 --- a/src/kernel/ao_motor_flight.c +++ b/src/kernel/ao_motor_flight.c @@ -52,6 +52,35 @@ static AO_TICK_TYPE ao_interval_end; uint8_t ao_flight_force_idle; +/* Compute ADC value change given a defined pressure change in Pa */ + +static inline int16_t +ao_delta_pressure_to_adc(uint32_t pressure) +{ + static const double volts_base = AO_PRESSURE_VOLTS_BASE; + static const double volts_max = AO_PRESSURE_VOLTS_MAX; + + /* Compute change in voltage from the sensor */ + double volts = (double) pressure / AO_FULL_SCALE_PRESSURE * (volts_max - volts_base); + + /* voltage divider in front of the ADC input to decivolts */ + double adc_dv = volts * (10.0 * (double) AO_PRESSURE_DIV_MINUS / + ((double) AO_PRESSURE_DIV_PLUS + (double) AO_PRESSURE_DIV_MINUS)); + + /* convert to ADC output value */ + double adc = adc_dv * AO_ADC_MAX / AO_ADC_REFERENCE_DV; + + if (adc > AO_ADC_MAX) + adc = AO_ADC_MAX; + if (adc < 0) + adc = 0; + + return (int16_t) adc; +} + +#define AO_BOOST_DETECT ao_delta_pressure_to_adc(AO_BOOST_DETECT_PRESSURE) +#define AO_QUIET_DETECT ao_delta_pressure_to_adc(AO_QUIET_DETECT_PRESSURE) + /* * Landing is detected by getting constant readings from pressure sensor * for a fairly long time (AO_INTERVAL_TICKS), along with the max being