Multiple ADCs using DMA on the RT1020

[tjhaeser]

On the RT1020, is it possible to sample multiple ADCs at the same time using DMA? If so, how many different ADC pins at the same time? I couldn't find anything conclusive in the manual.

I'd be immensely grateful for any nudge in the right direction.

[igorpadykov]

Hi TJ

seems this is possible as described in Chapter 15 ADC External Trigger Control (ADC_ETC)

i.MXRT1020 Reference Manual :

Capable of triggering dual ADC in SyncMode or AsyncMode:
• In SyncMode ADC1 and ADC2 are controlled by the same trigger source.

Best regards
igor
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[tjhaeser]

Hello, thanks for your input.

The issue is that we need to sample 6 ADC *pins* at the same time. The data is very time sensitive, so there should be next to no delay between the samples. We've tried a number of things, but so far were unable to do this.

[igorpadykov]

i.MXRT1050 ADC is a successive approximation ADC block, so by design

it is not possible to perform adc conversion simultaneously on all inputs. Conversion

is perfomed in sequence: first channel, then next, e.t.c.

Best regards
igor