This whole system feels so quirky and fiddly to work with compared to modern dev kits.
Turns out it's actually a bit more complicated. The Partner-N64 uses some little-used analog input pins (LAUDIO, RAUDIO, VIDEO_SYNC) for this. The modification also requires cutting the lines to the system's DAC chip to work.
https://ultra64.ca/tutorials/make-your-own-partner-n64-conso...
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