Multi-channel and sample saadc

[Judge]

Someone can help me. How to use multiple saadc channels simultaneously with 1 channel measuring many values ​​continuously in a short time?

[Karl Ylvisaker]

Hello, 

How to use multiple saadc channels simultaneously with 1 channel measuring many values ​​continuously in a short time?

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

[Judge]

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?

[Karl Ylvisaker]

Judge said:

Many thanks for your help.

No problem at all, I am happy to help!

Judge said:

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.

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