16 Jan
2016
16 Jan
'16
12:39 p.m.
On Jan 16, 2016, at 12:15, tony duell <ard at p850ug1.demon.co.uk> wrote:
I had considered that, or one of the TU58 emulators
that use SD cards or
similar but (a) I am trying to restore this VAX, not make a machine that runs
VAX software and is not original and (b) I do have this moral objection to
using more components to load the microcode than in the rest of the machine.
I am in that same camp. I am presently using TU58 emulation to make progress on the rest
of the system, but I do plan to try to get my original drive and tapes working in the
future. Even if I immediately unplug it and plug an emulator back in, because I thoroughly
distrust the tape cartridge design and I am not confident that any of my tapes are any
good. I would like to make an SD card based emulator that clicks into place in one of the
tape slots and the plugs into the console I place if the original drive, so it can be as
unobtrusive and standalone as possible.
AFAIK the TU58 interface (at least on the 11/730) can run at RS232 levels, you
don't need a level shifter board.
Correct. Regular RS232 levels. There is at least one really short timeout in the console
code that can cause trouble with some emulators running on some platforms, but I managed
to hack around that in tu58em running on a Mac. I put together hardware to use a RasPi
instead so the 730 doesn't need to be tethered to a laptop, but I haven't gotten
that working yet.
This, alas, means I am not going to have
ethernet since AFAIK you can't run the cable through that odd cable tray thing on
the 11/730.
I have Ethernet in my 730, though I don't have it working yet. My experience is that
trying to route the round AUI cable through the bottom tray with the ribbon cables is
doomed to failure, but the cable can instead be routed over the top of the cards, through
openings in the power supply area, then along the folding gantry along with the power
cables. I haven't gotten networking up and running on my VAX yet, and I don't yet
know what combination of hardware, software and operator ignorance is causing it to not
work. I'm still pretty happy that I can boot VMS from either the R80 or RL02.