On Sat, 26 Oct 2019, nico de jong wrote:
> As for documentation I have the CPU (only)
technical manual for the P850,
> the 2 volumes of schematics for the P851 and the preliminary manual (alas
> without the microcode source) for the P854. Some other schematics for
> things like the P854's PSU, the 4 channel serial port, floppy disk system,
> etc.
[...]
In order to test things, I've developped a
simulator and assembler for the
P857, although without floating point and I/O processor, as I have no
documentation for that, so maybe I can harvest something from the documents
you have. Are the mailable, or do you need to scan them first?
I have the P856M/P857M service manual online (actually for 11 years now ;-) )
It's the first hit from Google if you search for it.
This manual includes detailed description of the CPU, including the I/O
processor (appendix B), the MMU (appendix C) and the FPP (appendix D).
Christian