trick to use wav file (part-9 sound) about rpi4-osdev HOT 3 CLOSED

Oh, that's neat!

The (painful) alternative is to write the SDIO stuff required to get files off the SD card. That requires a whole world of code to read the FAT filesystem etc. (which is probably copyright M$!)

This is a rather great middle ground. Thanks for sharing!

I will try to add it to the docs at some point and credit you :) Unfortunately I've been distracted from this project for a little while - but my plan is to come back to it very soon. It's so much fun!

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That requires a whole world of code to read the FAT filesystem etc. (which is probably copyright M$!)

No, there are a couple (3 at least) of RPi baremetal FAT on SD/USB pieces of code in my repository list (which means it is/was here on GitHub somewhere), and I think at least one is in assembler - besides MS released FAT format to public, specifically for inclusion in Linux Kernel last year some time (2021 maybe 2020, after they bought GitHub - even tho its been in the kernel for 30+ years)

but if its in the ramfs filesystem you should not even need that .. just the wav file and the code to copy/play it from memory

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@paulwratt I must confess that I've got code for reading the FAT filesystem off the SD card... I just don't like/trust it enough to publish it! It was a pretty limited & clunky implementation as a proof of concept... I agree that this is not needed if we use the ramfs though. Weirdly I couldn't make @no-go's suggestion work. I suspect my brain was just on holiday that day (it happens!) and I haven't yet revisited it. I still really like the idea though which is why I left the issue open as a burning reminder 😄

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