16 Jul
2014
16 Jul
'14
3:22 p.m.
On 16 July 2014 11:58, Paul Koning <paulkoning at comcast.net> wrote:
You?d have to design an I/O model that the existing OSs support, or adjust
the OS code to fit your I/O model.
I was afraid of that! It seems most/a lot FPGA-based vintage computer
recreation projects get stuck at the I/O stage.
Apart from that, and as you point out the size of the
effort, it actually
helps a lot that the architecture is quite consistent and well documented.
The Architecture manual spells out what each instruction does, and what
all the other major blocks do, in a lot of detail and with substantial
rigor.
Yes! That is *definitely* helpful! I've been reading through DEC Standard
032, which has been immensely useful.
You might start with a PDP-11 as a warmup exercise ? that has the same
advantages but the I/O issue is way smaller and so is
the overall scope.
Well, not quite the same, but I've reading through the various open-source
PDP-11 implementations out there. Unfortunately, the one on OpenCores
wasn't too useful, as it is a hardwired design, which isn't really feasible
to do for a VAX.
Thanks for your suggestions!