21 Mar
2007
21 Mar
'07
11:30 a.m.
On 3/21/07, Patrick Finnegan <pat at computer-refuge.org> wrote:
On Wednesday 21 March 2007 11:33, Ethan Dicks wrote:
In the specific case of Qbus systems, you are correct. I was
(apparently unclearly) describing the general nature of PDP-11s,
PDP-8s, etc., with regard to boot ROMs to distinguish them from the
microcomputers that most people have had experience with. Yes, early
S-100 micros had front panels and might or might have had boot ROMs,
but for all pre-6100-microprocessor PDP-8s, one could have a boot ROM,
or a front panel, or both. A similar arrangement exists for Unibus
PDP-11s (boot ROM, or a front panel, or both).
I don't know of any front panels for Qbus machines, so perhaps I could
have been clearer in my explanation.
-ethan
(yes, in the mini-computer world,
boot ROMs aren't always integral - if you have a front panel, you
don't "need" ROMs, even if they are handy for fast startup).
True, but it's unlikely that any system with a KDJ11-A in it didn't have
some sort of boot ROM; there wasn't any front-panel that I know of for
those machines. The -A version was typically used in OEM gear which
had a boot-rom (or just a rom with the system's runtime code in it) on
some other board.