SymbOS - a multitasking OS and GUI for your Z80 machines

This project’s last update was 2017, but it seems to have got a good distance before going quiet. For CPC, MSX, PCW Joyce and Enterprise machines:

SYmbiosis Multitasking Based Operating System
Preemptive multitasking - 1024 Kb dynamic memory - 2 terabyte filesystem - 100% flexible windows GUI - network capable
available for your Amstrad CPC, MSX, Amstrad PCW and Enterprise 64/128

According to these facts, it’s a microkernel design.


That’s … impressive. 119,000 lines of Z80 assembler - 3.7MB of code.

Dedication for sure!


Very nice… supports quite a few hardware addons for the old beasties.

It is an impressive OS, but unfortunately, closed source. At one point I was looking for something new to put on an FPGA with my A-Z80 cpu in order to test it (and to see something different from the standard batch of retro designs) and could not manage to get the sources for this. In fact, all discussion groups, web pages etc. were appearing dormant, silent and dead to any new activity. Perhaps that changed recently?

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Ah, that’s always a shame, when something is created and then lost because it was hidden away.

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