djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

stm32/adc: Increase sample time for internal sensors on L4 MCUs.

Browse Source 
They need time (around 4us for VREFINT) to obtain accurate results.

Fixes issue #4022.
This commit is contained in:
Damien George 2018-09-20 23:51:33 +10:00
parent 3220cedc31
commit cb3c66e793
1 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
ports/stm32/adc.c
View File

@ -304,7 +304,13 @@ STATIC void adc_config_channel(ADC_HandleTypeDef *adc_handle, uint32_t channel)
sConfig.OffsetRightShift = DISABLE;
sConfig.OffsetSignedSaturation = DISABLE;
#elif defined(STM32L4)
sConfig.SamplingTime = ADC_SAMPLETIME_12CYCLES_5;
if (channel == ADC_CHANNEL_VREFINT
|| channel == ADC_CHANNEL_TEMPSENSOR
|| channel == ADC_CHANNEL_VBAT) {
sConfig.SamplingTime = ADC_SAMPLETIME_247CYCLES_5;
} else {
sConfig.SamplingTime = ADC_SAMPLETIME_12CYCLES_5;
}
sConfig.SingleDiff = ADC_SINGLE_ENDED;
sConfig.OffsetNumber = ADC_OFFSET_NONE;
sConfig.Offset = 0;