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by WalterBright 2248 days ago
I used to debug embedded systems by hooking an I/O pin to the speaker, then would toggle the pin level at various points in the program.

You could tell where it went wrong by the "song" after a while. Sorta like tuning your car by ear.
1 comments
hermitdev 2248 days ago
This reminds me of when I was helping a friend debug his home-built computer. Couldn't get a POST message out of it indicating why it wouldn't boot. After a while of searching, discovered it was because there wasn't a speaker connected to the non-existent pins for the speaker (there were no pins, just the soldering points for them). Once discovering that, used a multimeter to read the POST error - no GPU detected. Fun times...
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WalterBright 2248 days ago
> multimeter

Once I was introduced to an oscilloscope, I much preferred that. I bought a nice one off of ebay for about $60, and another peach of a scope from the pawn shop for $40.

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