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stmhal/adc: Make ADCAll.read_core_temp return accurate float value.

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It now uses factory calibration values to get a more accurate value, and
returns a float instead of an integer.
This commit is contained in:
Damien George 2016-11-30 12:05:53 +11:00
parent 87215a0f04
commit e72353cc48
1 changed files with 21 additions and 0 deletions
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21
stmhal/adc.c
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@ -60,18 +60,24 @@
#define ADC_FIRST_GPIO_CHANNEL (0) #define ADC_FIRST_GPIO_CHANNEL (0)
#define ADC_LAST_GPIO_CHANNEL (15) #define ADC_LAST_GPIO_CHANNEL (15)
#define ADC_CAL_ADDRESS (0x1fff7a2a) #define ADC_CAL_ADDRESS (0x1fff7a2a)
#define ADC_CAL1 ((uint16_t*)(ADC_CAL_ADDRESS + 2))
#define ADC_CAL2 ((uint16_t*)(ADC_CAL_ADDRESS + 4))
#elif defined(MCU_SERIES_F7) #elif defined(MCU_SERIES_F7)
#define ADC_FIRST_GPIO_CHANNEL (0) #define ADC_FIRST_GPIO_CHANNEL (0)
#define ADC_LAST_GPIO_CHANNEL (15) #define ADC_LAST_GPIO_CHANNEL (15)
#define ADC_CAL_ADDRESS (0x1ff0f44a) #define ADC_CAL_ADDRESS (0x1ff0f44a)
#define ADC_CAL1 ((uint16_t*)(ADC_CAL_ADDRESS + 2))
#define ADC_CAL2 ((uint16_t*)(ADC_CAL_ADDRESS + 4))
#elif defined(MCU_SERIES_L4) #elif defined(MCU_SERIES_L4)
#define ADC_FIRST_GPIO_CHANNEL (1) #define ADC_FIRST_GPIO_CHANNEL (1)
#define ADC_LAST_GPIO_CHANNEL (16) #define ADC_LAST_GPIO_CHANNEL (16)
#define ADC_CAL_ADDRESS (0x1fff75aa) #define ADC_CAL_ADDRESS (0x1fff75aa)
#define ADC_CAL1 ((uint16_t*)(ADC_CAL_ADDRESS - 2))
#define ADC_CAL2 ((uint16_t*)(ADC_CAL_ADDRESS + 0x20))
#else #else
@ -534,6 +540,16 @@ int adc_read_core_temp(ADC_HandleTypeDef *adcHandle) {
// correction factor for reference value // correction factor for reference value
STATIC volatile float adc_refcor = 1.0f; STATIC volatile float adc_refcor = 1.0f;
float adc_read_core_temp_float(ADC_HandleTypeDef *adcHandle) {
int32_t raw_value = adc_config_and_read_channel(adcHandle, ADC_CHANNEL_TEMPSENSOR);
// constants assume 12-bit resolution so we scale the raw value to 12-bits
raw_value <<= (12 - adc_get_resolution(adcHandle));
float core_temp_avg_slope = (*ADC_CAL2 - *ADC_CAL1) / 80.0;
return (((float)raw_value * adc_refcor - *ADC_CAL1) / core_temp_avg_slope) + 30.0f;
}
float adc_read_core_vbat(ADC_HandleTypeDef *adcHandle) { float adc_read_core_vbat(ADC_HandleTypeDef *adcHandle) {
uint32_t raw_value = adc_config_and_read_channel(adcHandle, ADC_CHANNEL_VBAT); uint32_t raw_value = adc_config_and_read_channel(adcHandle, ADC_CHANNEL_VBAT);
@ -597,8 +613,13 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_2(adc_all_read_channel_obj, adc_all_read_channel)
STATIC mp_obj_t adc_all_read_core_temp(mp_obj_t self_in) { STATIC mp_obj_t adc_all_read_core_temp(mp_obj_t self_in) {
pyb_adc_all_obj_t *self = self_in; pyb_adc_all_obj_t *self = self_in;
#if MICROPY_PY_BUILTINS_FLOAT
float data = adc_read_core_temp_float(&self->handle);
return mp_obj_new_float(data);
#else
int data = adc_read_core_temp(&self->handle); int data = adc_read_core_temp(&self->handle);
return mp_obj_new_int(data); return mp_obj_new_int(data);
#endif
} }
STATIC MP_DEFINE_CONST_FUN_OBJ_1(adc_all_read_core_temp_obj, adc_all_read_core_temp); STATIC MP_DEFINE_CONST_FUN_OBJ_1(adc_all_read_core_temp_obj, adc_all_read_core_temp);