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Comment by DonHopkins | Hacker News Reader

>(Here, for the “illegal” opcodes, we use the mnemonics used by the DASM and ACME assemblers, with the exception of “USBC” for instruction code $EB, where these use plain “SBC”.)

6502 assembly code is more sleek and beautiful and perfectly justified than most other assembly code, because all the opcode mnemonics are exactly three letters.

In comparison, assembly code in other CPU instruction sets looks so rough and messy, like the code was torn off along the right edge.

Kudos to the authors of that guide for respecting the lovely three letter convention for the illegal opcode mnemonics.

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I started as a teenager coding 6502 assembly on a Vic20. The three letter opcodes definitely made my code look beautiful.

Z80 assembly a few years later was a real disappointment. No doubt the instruction set was more powerful. But the code always looked ugly to me.

I've never forgotten my love for 6502 assembly. My mobile number ends with the 4 digits '6502'. <3

I started with the C64, and moved to an Amiga, and it felt effortless to move from the 6502 to a 68k. When I years later for the first time sat down with x86 asm it immediately motivated me to stop programming assembler.

Despite being incredibly dissimilar, the relative regularity of the 6502 and 68k felt familiar - a small set of rules and patterns flowed naturally into implementing quite complex code in a way it didn't on the x86. It's remarkable how much those things matters.

Exactly! Z80 code always looked "rough" to me, like its opcodes generated more friction while sliding through the CPU.

I don't have Obsessive Compulsive Disorder. I just think of it as Obsessive Compulsive Order.

Even though all its opcodes weren't 3 characters, the PowerPC really appeals to me as a clean, powerful, orthogonal, crystalline clear instruction set. I always visualized the PowerPC as Superman's Fortress of Solitude, the ice crystal palace with all the crisp 90 degree angles.

https://en.wikipedia.org/wiki/Fortress_of_Solitude

That's a cool mobile number! Was it intentional?

Almost as cool is the P.O. Box that Mitch Bradley coincidentally obtained for his Forth company:

    Mitch Bradley
    Bradley Forthware
    P.O. Box 4444
    Mountain View, CA 94040

https://groups.google.com/g/comp.lang.forth/c/cAFn_jDDu50/m/...

>Mitch swears the PO box number was totally coincidental!

Does he have problems with Asian customers? (4 is the unlucky number)

Yep! I was buying a special mobile number for my partner, and spotted the 6502 one. What makes my number extra special (to me) is it is "06 <year of birth> 6502".

I actually considered inventing a new three-character one for "USBC" (maybe "SNC" for "SBC+NOP"?), but thought it would be better to not to add to the existing confusion regarding the names of these undocumented instructions. (Some of them have a long history, not all of them are perfectly chosen, but they are what they are.) The same applies to "ANC" and "ANC2": is the distinction of these externally similar instructions really worth ruining the simplicity and beauty of the three-letter convention?

There's probably at least one 6502 assembler out there that dissassembled $0A/$4A as "ASLA"/"LSRA" instead of "ASL A"/"LSR A" or just "ASL"/"LSR".

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