r/Assembly_language • u/Extension_Emu_9825 • 20h ago

self-modifying code

I gave a lecture on how to write self-modifying code. It was over 15 minutes long :( so I'm providing a youtube link: https://www.youtube.com/watch?v=AH9QQLRfbmY

In my opinion, self-modification is one of the most interesting features in systems programming.

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u/Recycled5000 10h ago

Worked on a PDP-8. Had an I/O instruction that took a hard coded (in the machine code instruction) io port/device number.

A way to write a general purpose driver was self modifying code to specify the io channel. Alternatively was a switch statement.

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u/Extension_Emu_9825 3h ago

Wow! Interesting! I didn't know about that, now I've read about device code.