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I'm trying to get this: is it that the TRS-80 had lowercase in ROM, and the logic to produce it, but since chip 8 was missing, bit 8 (upper/lower) would always be zero? that's electrically plausible but is that really what they're saying
it's always buck wild to me that computers of this era could tolerate gross abuse of their buses and simply march on undeterred. modern computing is so complex that essentially every part of the computer is being touched at all times, and any failure anywhere will cause collapse
that c64 bus expander I posted earlier, with the *fuse* on it - that was like walking into what I thought was a steakhouse and the door guy slams me against a wall and demands that I hand over my gun before I can be seated
like to me, that's the point where I just go home. switches physically installed in the middle of the literal data bus? are you having a piss of me mate. It's absurd, you can't imagine trying to pretend you're having a normal dinner with that nonsense going on.
looking at the *pushbutton* installed on an *address line* is like walking in to taco bell and someone's bleeding out on the counter. It's 911, it's a ruined day, there's no recovering. There's no making this normal. It's beyond any etiquette I can imagine.
it's not how it's done, in the same way that you don't make a purchase at a grocery store by throwing a wad of cash at a cashier's face. It's so far beyond the extremely precise but *universally understood* basic rules of society that it's completely arresting to see.
buses are internal. everything that touches them is heavily vetted by an electrical engineer and does not reach your hands if there's the remotest chance of catastrophic failure, and if it DOES fail, the current is limited somewhere
you can't put switches on an address bus. first because that's absurd, it's just meaningless. I mean really, that's nothing, that's gibberish. what? that's sugar in a gas tank
that's not how this works, those lines aren't dedicated purpose, they aren't labeled "kitchen lights" and "ceiling fan." these are the neural pathways of the computer and you're just swapping them around? no! it'll crash! it won't execute anything!
you can't circuit bend a modern computer. they just freeze, because fucking with a single wire means trashing the transport for millions of multiplexed signals. Everything does infinite jobs at once
but on a computer from 1977... you can just remove an entire ram chip, because that chip is hardwired to do exactly one thing and cannot ever do anything else. it is fully known what it does. all tasks it will ever have are documented. it is a chip that stores Case.
things were not better. but they were smaller, and our brains could kinda get them.
if you're reading this in the future here's the horrible gremlin i am describing
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