New batch of pdp8 OMNIBUS to USB interface! Please Read and react!

Philipp Hachtmann hachti at
Sun Feb 19 05:51:44 CST 2017

On 17.02.2017 23:47, Charles Dickman wrote:
> What I am wishing for are Omnibus and Unibus adapters to an FPGA.

I also thought about that. As a lab tool I'm totally fine with plugging 
anything into my 8 or 11.

This could be done much easier for the Unibus than for Omnibus!
  In fact I first thought about making a universal Omnibus interface. 
Then I realized that it would have taken a massive amount of drivers and 
receivers because every peripheral can use/manipulate so many signals on 
the bus. And at that time I wanted to have
It's not address decoding and data lines, it's about data break, CPU 
control lines and so on. The Omnibus contains much CPU-internal stuff 
which *might* be usable or used for a certain interface board.
A peripheral board can force the CPU to continue at any address for 

The pdp8 external IO bus or the Unibus are more clear: You need this, 
that and that. And that's it.

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