Re: OpenBSD on the VXT2000

[...]
> 
> Is there any interest at all in supporting the VXT2000, or should I
> just forget this?
> 
I have looked at it some time ago. It would probably be possible to make
it run at least with serial console. The main problems are:

- The machine is not made to run a "real" OS, so as soon as anything is
  done "wrong" it will hang hard and need power recycling.
- Memory is not contiguous. My machine has 0-2MB and 4-10MB, so there is
  a hole. It may vary between different machines and different amount of
  memory.
- It seems to be only one interrupt level and one interrupt vector that
  is in use, and it tend to be edge-triggered, so it's easy to loose
  interrupts.
- Driver for the console serial port must be written. It's not a DZ11-
  lookalike as on the other machines, but a SC26C94 UART. 
- No docs, everything is trial-and-error.

I think that the cpu otherwise implement a complete enough instruction
set to be able to run NetBSD on it.

-- Ragge