Posted on June 21, 2017 at 12:55Hello.
There was a problem with the operation of the ADC with built-in thermistor and VBAT voltage.
The value 4095 is always read.
Here is an example of code for reading voltage VBAT:
/* Configure the ADC clock */
RCC_ADCCLKConfig(RCC_ADC12PLLCLK_Div2);
/* Enable ADC1 clock */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_ADC12, ENABLE);
/* Setup SysTick Timer for 1 �sec interrupts */
if (SysTick_Config(SystemCoreClock / 1000000))
{
/* Capture error */
while (1)
{}
}
ADC_StructInit(&ADC_InitStructure);
/* Calibration procedure */
ADC_VoltageRegulatorCmd(ADC1, ENABLE);
/* Insert delay equal to 10 �s */
Delay(10);
ADC_SelectCalibrationMode(ADC1, ADC_CalibrationMode_Single);
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1) != RESET );
calibration_value = ADC_GetCalibrationValue(ADC1);
Delay(100);
ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_CommonInitStructure.ADC_Clock = ADC_Clock_AsynClkMode;
ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
ADC_CommonInitStructure.ADC_DMAMode = ADC_DMAMode_OneShot;
ADC_CommonInitStructure.ADC_TwoSamplingDelay = 0;
ADC_CommonInit(ADC1, &ADC_CommonInitStructure);
ADC_InitStructure.ADC_ContinuousConvMode = ADC_ContinuousConvMode_Disable;
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ExternalTrigConvEvent = ADC_ExternalTrigConvEvent_0;
ADC_InitStructure.ADC_ExternalTrigEventEdge = ADC_ExternalTrigEventEdge_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_OverrunMode = ADC_OverrunMode_Disable;
ADC_InitStructure.ADC_AutoInjMode = ADC_AutoInjec_Disable;
ADC_InitStructure.ADC_NbrOfRegChannel = 1;
ADC_Init(ADC1, &ADC_InitStructure);
ADC_RegularChannelConfig(ADC1, ADC_Channel_Vbat, 1, ADC_SampleTime_7Cycles5);
ADC_VbatCmd(ADC1, ENABLE);
/* Enable ADC1 */
ADC_Cmd(ADC1, ENABLE);
/* wait for ADRDY */
while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_RDY));
/* Infinite loop */
while (1)
{
ADC_StartConversion(ADC1);
/* Test EOC flag */
while(ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC) == RESET);
/* Get ADC1 converted data */
ADC1ConvertedValue =ADC_GetConversionValue(ADC1);
/* Compute the voltage */
ADC1ConvertedVoltage = (ADC1ConvertedValue *3300)/0xFFF;
printf('ADC1ConvertedValue = %d\r\n',ADC1ConvertedValue);
}
Reading the temperature sensor is similar, only the ADC channel selection differs:
ADC_RegularChannelConfig(ADC1, ADC_Channel_TempSensor, 1, ADC_SampleTime_7Cycles5);
ADC_TempSensorCmd(ADC1, ENABLE);
In both cases, the ADC returns a value of 4095.
What am I doing wrong?
In the attachment - the whole project:
adc_std_01.rar -
VBAT measurement design
adc_std_02.rar -
Temperature measurement project
adc_01.rar -
A temperature measurement project assembled in CubeMX using HAL
adc_02.rar -
VBAT measurement design, assembled in CubeMX using HAL
Thanks in advance.
#temperature-sensor #stm32f303 #stm32f303-adc #vbat-monitoring
