Hacker News new | ask | show | jobs
by vidarh 929 days ago
Less impressive, but something which was still fun to me when I had an Amiga: At least some Amiga keyboards used a SOC with a 6502 core.

One of my Amiga's had 4 CPU families: A 6502 core on the keyboard, a Z80 on the SCSI controller, an x86 on a bridge board (the Amiga 2000 had ISA slots, and one of them was in-line with a Zorro slot so you could get a board that let you run x86 software using a window on the Amiga desktop as the output; I don't remember if the bridge board itself was an 8088 or 8086, but I upgraded it with a 286 accelerator card) and of course the 68000 (+ a 68020 expansion)....

Looks like it's this one I remember:

https://www.amiga-stuff.com/hardware/6500_1.html

2 comments

The ABC computers used a Z80 in the keyboard and a Z80 as main CPU. Weird times. :)
The 1541 floppy drive for the C64 used a 6502, almost the same as the C64’s 6510 CPU. Some C64 software co-opted the floppy drive’s 6502 as a coprocessor.
There's a demo that plays entirely out of the 1541, you can disconnect the rest of the computer: https://youtu.be/zprSxCMlECA
I've seen that one before, but always love seeing this. And particularly love the touch of not using pre-prepared cables but casually unplugging the C64 and cutting apart and splicing the cables with the equipment on...
The 4040 drive for the Commodore business line had TWO 6502 equivalent CPUs. I used to tease a friend who owned one that his floppy drive was smarter than his computer.
> Some C64 software co-opted the floppy drive’s 6502 as a coprocessor.

In that sense, the 8-bit Commodores were a bit like mainframes - one could load a data transform program to run on the floppy drive and run it without bothering the host. I believe it goes a bit further than the Atari family in that.

Now I got curious: I have the impression the 2000 wouldn't be able to see the ISA bus unless a bridgeboard with an x86 was there. Is that so or could the 2000 see the ISA boards regardless of the bridge board?
That is correct, power only. Even with the bridge board installed the Amiga bus could not talk directly to the ISA side, any communication went through dual port ram on the bridgeboard - signals were in no way multiplexed between the two buses directly.
Such a missed opportunity... It'd have allowed Amigas to easily tap the graphics hardware becoming available to ISA machines. Even a plain (and cheap) bridge board with just the bus interfaces would be a huge enabler that could take the Amiga out of its multimedia (and NTSC-timings) niche.
I believe you're right that it can't see it without the bridge board.