Why do you think Wozniak would care? Man is a multi-milionaire on account of his Apple shares, and has better things to do these days than bum single bytes out of 6502 code ;)
My post is made for the benefit of current and future 6502 programmers.
I guess you must not be a 6502 programmer, because if you were, your response would be, like, "dude, fuck, that's awesome, holy shit, let me take some notes". Because that was what my response was the first time I saw this code. And that's why I'm passing it on.
6502 zeropage addressing effectively made it a risc by today’s standards. Done right it made for fast and compact code.
Sometimes I’d throw in an extra instruction as alternate entry point into a subroutine. We’d be scrounging for ROM space and would adhoc a subroutine into the end of a different one.
Time delays were another good reason. An extra cycle mattered when you needed to sync with something.
Made for fun times when debugging but you did what you did.
> I guess you must not be a 6502 programmer, because if you were, your response would be, like, "dude, fuck, that's awesome, holy shit, let me take some notes".
It is weird, isn't it? You might almost think that I just typed out the first thing that sprang to mind, and then clicked 'reply', without even wondering whether it made any sense... well, I couldn't possibly comment.
But I do stand by what I said, no matter how much its actual value might be in line with what you paid to see it. Wozniak is massively rich because of his Apple shares, and I claim that does indeed limit his interest in bumming single bytes out of some 6502 code he wrote 40 years ago. And I do also claim it limits how concerned he might be that somebody had spotted some slack in his code.
While I'm on this theme, in fact let me guess that you are not a 6502 programmer yourself either ;) Because if you were, even if you'd never seen the nybble->hex trick before, even if you were actually seriously all like "dude, fuck, that's [etc.]" - not that this isn't a reasonable response to this trick, because it is awesome, and rather surprising - you'd still at least be very well aware that in 2018 this is a hobby that even its devotees, e.g., me, would freely consider quixotic. (And that's being very generous.) And you would therefore appreciate the humour.
