Multi-channel and sample saadc

RE: Multi-channel and sample saadc

Karl Ylvisaker — Mon, 06 Sep 2021 17:07:22 GMT

[quote user="YuhQPL"]Many thanks for your help.[/quote]

No problem at all, I am happy to help!

[quote user="YuhQPL"]Like you say here I use 1 channel ADCVDD and 1 channel AIN4, I want to sample at AIN4 channel every 5 minutes and measure continuously 10 values each time.[/quote]

Thank you for clarifying. How often will the VDD be sampled?
If you intend to have the samplings happening at different frequencies using only the internal SAADC timer (no PPI + TIMER instances) you will have to un-init and re-init the SAADC every 5 minutes. You could then have the SAADC use BURST (and possibly oversampling, if this is your intention) on the AIN4, to quickly collect and average the AIN4 measurements, before re-initializing to sample the VDD at a different frequency.

How does this sound, would it fit the constraints of your application?
If not, please elaborate more on the constraints and sampling frequencies so I may better understand your intention and issues.

Best regards,
Karl

RE: Multi-channel and sample saadc

Judge — Mon, 06 Sep 2021 16:07:33 GMT

Many thanks for your help. Like you say here I use 1 channel ADCVDD and 1 channel AIN4, I want to sample at AIN4 channel every 5 minutes and measure continuously 10 values each time. i don't want to use ppi because currently my app is using on mesh network. Don't know if you have any ideas for this?

RE: Multi-channel and sample saadc

Karl Ylvisaker — Mon, 06 Sep 2021 07:51:37 GMT

Hello,

[quote user=""]How to use multiple saadc channels simultaneously with 1 channel measuring many values continuously in a short time?[/quote]

To sample multiple channels sequentially you must use the scan mode of the SAADC.
Could you elaborate on what you mean by the last part - are you looking to have oversampling + burst mode on a single channel? Or do you mean that you would like to have one of the channels sample more often than the other channels?

Best regards,
Karl