3 ms·
I still have a Commodore 128 that has a second Z80 CPU just for running CP/M. Really weird in retrospect.
by spullara 10y ago
I still have a Commodore 128 that has a second Z80 CPU just for running CP/M. Really weird in retrospect.
- thwarted 10y agoI've rarely used the C128 mode in VICE, but according to the manual[1], x128 emulates a z80 too. It would be kind of cool to develop in linux and then "deploy" the code to x128's z80 emulator as a "production" environment. [1] http://www.cs.cmu.edu/~dsladic/vice/doc/html/vice_2.html#SEC7 http://www.cs.cmu.edu/~dsladic/vice/doc/html/vice_2.html#SEC...
- sedatk 10y agoSpeaking of weird chips from that era, Amstrad CPC464's sold in Spain came with an extra 8KB RAM on board that was not connected to anywhere. It was put there only to avoid import tax for computers with 64KB RAM or less.
- nsxwolf 10y agoMicrosoft's first hardware product was a Z80 add on board for the Apple II, which served the same purpose.
- digi_owl 10y agoEven as late as the Amiga you got stuff like that. To this day you can probably find a PPC based accelerator for all models. I guess the close to the metal, with little to no memory protection barriers, made these kinds of things easy to implement. That said, some early GPUs were somewhat similar. The 3DFX cards used pass through VGA cabling. And i personally owned a PowerVR card that wrote rendered frames back to the graphics card over the PCI buss.
- zwieback 10y agoApple ][ with a Z80 card was a similar setup I used, mainly for Turbo Pascal and dBase.
- Feneric 10y agoIIRC the Z80 would be the first processor to wake up, too, and would retain control CP/M were being used but would shift control over to the other processor if either native or C64 mode were being used.