16 Jul
2014
16 Jul
'14
11:19 a.m.
On Jul 16, 2014, at 1:58 PM, Paul Koning <paulkoning at comcast.net> wrote:
On Jul 16, 2014, at 1:49 PM, Kevin Keith <krfkeith at gmail.com> wrote:
Indeed; the first option is generally way easier. To get started, the console
SLU is actually pretty simple hardware; you could get basic processor booting
with that. Further devices increase significantly in complexity; for any MSCP
devices, you almost certainly want some sort of processor running, but basic
SCSI chips like those used in early VAXstations aren't so bad (I think a lot
of the early 3100s used the 53C80, which is dead simple because it's mostly
just a buffer).
A console SLU and an appropriate boot ROM (assuming you're implementing a
particular CPU bug-for-bug) will actually get you a lot of the way.
Everything else is an optional peripheral, for varying definitions of the
word "optional". :-)
- Dave
Basically, my question is what are the major
obstacles (besides the breadth
of the project) to implementing the VAX in an FPGA, as compared to any
other ISA?
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.