I have posted a high speed analog pin to SD logger here Try this super fast analog pin logger - Storage - Arduino Forum.
I posted it under storage since most of the code is related to the SD.
I tested it by logging five pin samples at 5,000 samples per second or 25,000 ADC values per second.
I also did single pin tests at 40,000 samples per second.
Please post post any comments at the above location.
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