[corysama]

I can tell you that for 3rd party titles back in the PS2/N64 days, the HW engineers handed you a spec manual explaining such useful things as "Bit 7 at address 0x70002048 toggle RFTAG mode on the MDEC". This was great when I went to write a VU emulator because no VU debugger was available. But, not so great when trying to figure out how to use the beast effectively. If you google "ps2 sdk docs" you can still find them after a while. If it's a doc with examples of how to do anything, it's from the software team at Sony Europe.

Sony Japan's documentation for how to use a mouse & keyboard on the PS2 was literally just the URL "https://www.usb.org/document-library/usb-20-specification". Eventually, they provided a binary-only keyboard library that everyone complained was buggy, but actually just had documentation that was so brief it was easily misunderstood. After black-box testing it for an hour it was clear it worked fine, just not how anyone would expect it to.

Many years ago I made a tiny stir online by writing a stream-of-consciousness report of the experience of dealing with stuff like this for a decade. https://venturebeat.com/games/what-is-making-games-like-for-...