Comment by dhosek

Comment by dhosek 8 days ago

The Wozniak method was how I used to write 6502 assembler programs in high school since I didn’t have the money to buy a proper assembler. I wrote everything out longhand on graph paper in three columns. Addresses on the left, a space for the code in the middle and the assembler opcodes on the right, then I’d go through and fill in all the hex codes for what I’d written. When you work like that, it really focuses the mind because there’s not much margin for error and making a big change in logic requires a lot of manual effort.

mfuzzey 8 days ago

I started Z80 assemnbler (on a ZX80 computer) that way. But I soon get fed up looking up opcodes and especially calculating relative jumps (especially backwards ones) by hand as I often seemed to make off by one errors causing my program to crash.

So I wrote my on assembler in BASIC :)

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dhosek 7 days ago

I wrote a Z80 disassembler that was, alas only partially complete as it didn’t handle the two-byte opcodes as part of my efforts to reverse engineer the MSX Spectravideo computer I got in exchange for writing some demo programs for the midwest distributor while I was in high school. I remember finding the memory locations of the character bitmaps by doing wholesale poke commands through the whole memory of the computer.

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