Posted on February 23, 2018 at 14:03Hi Guys,
am using STM32f429, trying to read internal temperature sensor which is configured to ADC1 ADC_CHANNEL_18,
am able to read temperature readings,but my device is giving 70 deg/C .
am not able to find why the device is giving temperature that much high, following is the code which am using,
#define ADC_CHANNEL_DIFFERENCIATION_TEMPSENSOR_VBAT 0x10000000U
#define ADC_CHANNEL_TEMPSENSOR ((uint32_t)ADC_CHANNEL_18 |ADC_CHANNEL_DIFFERENCIATION_TEMPSENSOR_VBAT)
#define ADC_CHANNEL_VREFINT ((uint32_t)ADC_CHANNEL_17)
#define ADC_CHANNEL_VBAT ((uint32_t)ADC_CHANNEL_18)
void TempINIT(void){
ADC_ChannelConfTypeDef sConfig;
AdcHandle.Instance = ADC1;
AdcHandle.Init.ClockPrescaler = ADC_CLOCKPRESCALER_PCLK_DIV2;
AdcHandle.Init.Resolution = ADC_RESOLUTION12b;
AdcHandle.Init.ScanConvMode = DISABLE; /* Sequencer disabled (ADC conversion on only 1 channel: channel set on rank 1) */
AdcHandle.Init.ContinuousConvMode = DISABLE; /* Continuous mode disabled to have only 1 conversion at each conversion trig */
AdcHandle.Init.DiscontinuousConvMode = DISABLE; /* Parameter discarded because sequencer is disabled */
//AdcHandle.Init.NbrOfDiscConversion = 0;
AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE; /* Conversion start trigged at each external event */
AdcHandle.Init.ExternalTrigConv = ADC_SOFTWARE_START;//ADC_EXTERNALTRIGCONV_T1_CC1;
AdcHandle.Init.DataAlign = ADC_DATAALIGN_RIGHT;
AdcHandle.Init.NbrOfConversion = 1;
AdcHandle.Init.DMAContinuousRequests = DISABLE;
AdcHandle.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
if (HAL_ADC_Init(&AdcHandle) != HAL_OK)
{
/* ADC initialization Error */
Error_Handler();
}
/*##-2- Configure ADC regular channel ######################################*/
sConfig.Channel = ADC_CHANNEL_TEMPSENSOR ;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
if (HAL_ADC_ConfigChannel(&AdcHandle, &sConfig) != HAL_OK)
{
/* Channel Configuration Error */
Error_Handler();
}
ADC->CCR &= ~ADC_CCR_VBATE;
}
uint8_t GetTempValue(float *TempValue_degC) {
unsigned short int count;
uint32_t Adc_Value =0;
uint32_t Adc_Value2 =0;
float vsense=0;
float samples =0;
float Temp;
TempINIT();
for(count=0;count<20;count++) {
HAL_ADC_Start(&AdcHandle);
if (HAL_ADC_PollForConversion(&AdcHandle, 1) == HAL_OK) {
Adc_Value = (uint16_t)HAL_ADC_GetValue(&AdcHandle);
Adc_Value2 =Adc_Value;
samples+=Adc_Value;
}
else {
Adc_Value = 0;
return ERROR;
}
HAL_ADC_Stop(&AdcHandle);
}
samples = samples/20;
vsense = ((samples)*(3300))/4096;
Temp = (((vsense) - (760))/(2.5)) + 25;
*TempValue_degC = Temp;
Adc_Value = 0;
samples = 0;
return SUCCESS;
}
/**
Thanks In Advance
with regards,
Himasagar.
