KEYBCS2

os2museum.com

18 pointskencausey2 comments

The last processor generation it worked on is the 486, but on a Pentium or newer it always fails with a “Debugging is not allowed” message.

I guessed the reason for that correctly - prefetch queue. Mentions of CUP386 in the comments also brought back more memories of the cracking scene in the late 80s/early 90s. There's some very interesting discussion on SMC vs CPU behaviour here --- in the context of an open-source 486-level SoC core:

https://github.com/MiSTer-devel/ao486_MiSTer/issues/33

Back when custom code pages seemed entirely normal heh.

Really amazing archeological work here.

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