diff options
| author | Damien George <damien.p.george@gmail.com> | 2018-09-20 23:51:33 +1000 |
|---|---|---|
| committer | Damien George <damien.p.george@gmail.com> | 2018-09-20 23:51:33 +1000 |
| commit | cb3c66e79358f03367d0b4e5d2b6ec649ac29733 (patch) | |
| tree | 437aafb66f0889e9e4b181aaaa690d6fc6432527 | |
| parent | 3220cedc31f2ce161286baf58cfdfd396697348a (diff) | |
stm32/adc: Increase sample time for internal sensors on L4 MCUs.
They need time (around 4us for VREFINT) to obtain accurate results.
Fixes issue #4022.
| -rw-r--r-- | ports/stm32/adc.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/ports/stm32/adc.c b/ports/stm32/adc.c index c20e1bca4..f16159bef 100644 --- a/ports/stm32/adc.c +++ b/ports/stm32/adc.c @@ -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; |