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Fast ADC Readings
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Fast ADC Readings

by andymanic on Tue Jul 27, 2021 11:55 am

Hi there, I'm probably being stupid but I was hoping for a little help getting fast ADC readings from the ItsyBitsy M4. I've seen the forum & github posts about the adafruit arduino core running at 250k SPS, but can't find any example sketches for how to achieve that. I'm looking to get 100kSPS, but some posts suggested that the analogReadFast() takes 21us on the SAMD21, which would be more like 47kSPS. I don't have the underlying knowledge to know what I'm looking at yet. Any guidance would be greatly appreciated, thanks.

andymanic
 
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Re: Fast ADC Readings

by mikeysklar on Tue Jul 27, 2021 7:39 pm

@andymanic,

Have you looked into the Sync Busy register for the SAMD51? It looks like it was just a bit with the SAMD21 (M0) and now an entire register for the SAMD51 (M4). I think the idea is to kick off the next ADC read as soon as SYNC busy is cleared.

https://community.atmel.com/forum/cant- ... sybitsy-m4

mikeysklar
 
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Please be positive and constructive with your questions and comments.