STM CircleOS forum / Using ADC under OS

PK · 2009-03-30 07:26:38

Hi,
I tryied to using ADC CHannel0 to measure external voltage. In my application
under OS I made new ADC_Init and new DMA_Init. I used the same DMA channel1 like
Battery & TempSensor. It work but the readed voltage is unstable.
What the problem could be with configuration? Should I use another DMA channel?

PK

Francis · 2009-03-30 09:33:38

It could be the input capacity of the ADC. If you switch very fast from one input to the next, the second value can be wrong. A solution could be to add dummy measurement of your input (and to discard the first data that could be corrupted by the last selection).

PK · 2009-03-30 11:00:57

I used circular measurement of 1 channel (ADC_NbrOfChannel )= 1....
But now I checked average of 4 measurements and it is quite stable.
How large could be a total error of conversion? For example, my voltmeter shows 1,52V
and Primer after calibration shows 1,50V.
It is correct?

# 1 2009-03-30 07:26:38 Using ADC under OS

Using ADC under OS

# 2 2009-03-30 09:33:38 Using ADC under OS

Re: Using ADC under OS

# 3 2009-03-30 11:00:57 Using ADC under OS

Re: Using ADC under OS

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