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One of the biggest disappointments of the 8-bit era was the Commodore 128 not being able to use both the 8502 and Z80 CPUs in some kind of coprocessor setup.
by Mountain_Skies 1y ago
One of the biggest disappointments of the 8-bit era was the Commodore 128 not being able to use both the 8502 and Z80 CPUs in some kind of coprocessor setup.
- timbit42 1y agoThe Commodore 128D has two 6502 CPUs. One is in the floppy drive and you can run software on it while the main 6502 ran something else.
- mschaef 1y agoThat derives logically from the way Commodore implemented disks. If you bought a 1540 or 1541 (or any other Commodore drive) for a C-64 or VIC-20, it had an onboard 6502 to run the disk drive. The interaction between the computer and the disk drive was somewhat similar in concept to fetching a file from a network server. This could be useful to save on costs in computer labs... my grade school used multiplexer boxes to share a single 1541 across four C-64's.
- Joe_Cool 1y agoIt was always awkward to do low level disk stuff by basically "remoting" into the drive to execute code. OPEN 1,8,15,"N:NEWDISK,01":CLOSE 1 was always a weird way to format a floppy...
- mschaef 1y agoKnowing what I know now, I'd have appreciated it much more than I did at the time. (Also, fixing the link rate on the C64 would've been nice too.)
- rasz 1y ago128D had 3 cpus :)
- GlenTheMachine 1y agoI wrote code to do this between a C64 and a 1541 disk drive when I was in high school. It got me to the international science fair and (probably) earned me a full tuition scholarship for undergrad.