Homebrew Meets Business Computing

I found this somewhat interesting and curious:

In 1982, Commodore (or rather, CBM) released the CBM II as a successor to the PET, a serious business machine running on a 6502 6509 at 2MHz with an ample 256KB of RAM at its disposal. But, as luck would have it, IBM had entered the market with the 1550 and MS DOS was the new hot thing. So Commodore designed an Intel 8088 daughter card to provide DOS compatibility, but, as it turned out soon, DOS compatibility alone wasn’t enough. What it really took was PC hardware compatibility, something this solution couldn’t provide. (Which was apparently also the end of the DOS card.)

This is, where Michal Pleban comes in: Can we accomplish in 2021 what Commodore couldn’t do back in the day by some clever software hacks in best homebrew tradition and bring actual PC software to the CBM II?

Software and hardware schematics for an enhanced version of the original 8088 card are available on GitHub and there’s also a dedicated website, according to which ready-built boards will become available in Q3 2021.

http://www.cbm-ii.com

https://github.com/MichalPleban/cbm2-pc-emulator/
https://github.com/MichalPleban/cbm2-8088-ram-board/

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Ah, interesting! This reminds me of a hack that allowed CGA graphics work on Hercules Graphics (monochrome only, of course). This is how I played Sopwith. It had a certain lag to the “emulated” scanlines that were periodically copied over … this created visible “spikes” to terrain when horizontally scrolling. But it worked well enough.

Commodore tried so many hacks to provide some level of PC compatibility or CP/M on so many platforms … obviously also including Commodore Europe even making some PC clones … but other than those clones, they were just too slow and limited and comparatively expensive to succeed.

Just in time “8-Bit-Show-And-Tell” released a video on that CBM line on YouTube:

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