2 Nov
2005
2 Nov
'05
5:31 p.m.
There is another difference, the 9845C were shipped
with colored=20
functions keys ;-)
What, all different colours, to indicate the colour that the text (or=20
whatever) will appear on the monitor? The HH Tiger did that.
> Thanks, I'm glad my PSU is still working.
I've had enough trouble with=
=20
> the 9845A PSU, which is only as half as
complex, although the function=
al=20
=20
When you say 'half as somplex', do you mean it only has one main choppe= circuit, not the 2 that are used in the 9845B Opt
200?
I have never seen a 9845A, but from what I've heard it's very different=
=20
to the B or C. To the extent that both processor
modules are on one PCB=
,=20
and there's a bus switching board alongside
it.
=20
Yes and no. The mainboards connectors and the output voltages of the PSU=20
are the same. Even the mechanical PSU assembly is the same, with the=20 The color monitor has just enough space for one
additional board, the=20
light pen controller. Since I don't have the controller board, I=20
currently don't care much about a light pen, although it would be nice=20
I don't have one either. It would be nice to find for completeness (if
only to 'complete' the schematics), but....
It's clear the light pen was fairly hardware-intensive. Many of the video
timing signals, including the outputs from the horizontal counter on the
text PCB, go to the light pen controller.
to see how it works. However I got a working graphics
9111A tablet,=20
thats ok for now. Even a hopefully working 8"-floppy. So data transfer=20
A 9885? I have a few of those....
My 9845B came with a 3rd party mass storage ROM module. I am told this
allows the use of HPIB disks (probably Amigo protocol). The main use of
it so far has been due to the fact that it was a little PCB with normal
chips on it, not an HP hybrid. Very useful for figuring out what the ROM
module connections are.
would be (theoretically) possible as well. When I get
one of those=20
&#$=A7*-9845 working.
they actually
do there. I have now seen the HP boardwapper guide for th=
e=20
monitor, but I couldn't easily work out the
translation between my name=
s=20
and HP's.
=20
In case I get a copy of the schematics, I will try to help. Actually,=20