I understand that the extra 2MB of memory is for circuit python. However, I wouldn’t mind having access to 2MB of storage and using the Arduino IDE/low level C to access it. Is that possible? If so, how?
In their guided tour of the Adafruit Circuit Playground Express, it specifically states:
You can use this in Arduino or CircuitPython to store files.
So yes, it is possible. As far as the how, according to this guide (also from Adafruit), that they have also made a library, Adafruit SPI Flash, which has a bunch of examples showing how to read from, write to, and format the SPI flash whilst retaining compatibility with CircuitPython, among other things.
Correct answer by Peter Feerick on December 4, 2020
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