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jonjackytoday at 6:04 PM1 replyview on HN

I think after a day or two of full immersion in this environment, disassembling hex code would be mostly straightforward. Woz is said to have 6502 binary memorized. It doesn't really take much, you don't need to memorize it all. Knowing a dozen instructions can take you a long way.

It does. I am certainly no Woz, but I used to program a KIM-1 by hand assembling with pencil and paper from a programming card, then keying hex codes into its onboard keypad. After a few days you don't need to look at the card much. It's really quite practical - it's actually easier than dealing with editor and assembler tools. After fifty years, I still recall that A5 encodes LDA.


Replies

drob518today at 6:16 PM

Agreed, though I would say that 6502 is a lot more straightforward to memorize than x86. A lot fewer addressing modes and every instruction is always just a byte, possibly followed by immediate data. The 6502 was a little gem.