22 May
2012
22 May
'12
5:34 p.m.
On 18/05/2012, at 5:17 AM, Tony Duell wrote:
Toni, I was expecting that kind of reply : ) I've been lurking on the list for long
enough to know..
Unfortunately I don't have much spare time at the moment, I'm in the middle of
renovating my house, so these machines will have to wait a while if I'm doing board
level repairs (or any repairs for that matter). Another issue is that I'm rather
short of bench space, which will be much better when the house is finished (and my
collection of old motor scooters is out of the way).
It is a spare memory box for a 9820. It does not have a complete set of cards though,
only has one each of blue, green, yellow, and orange.
When I get more time and space I will get back the these machines and let you know what I
find.
Chris.
in depth)
information, I'm sure it's going to be a lot of help.
Initially I think I will probably just clean up the 9810 and one 9820
and board swap (if necessary). I'll sort out th rest at a later date.
You do want me to carry on talking to you, right? :-) Oh, I guess you're
new here and haven't been o nteh end of my antiboardswap[ing rant.
No, I am not going to repost it. All I am going to say is that tese are
fine machiens nad deserve to be fixed properly. And that means amking
measurement,s thinking aobut thosie measurements and then deducing what
the fault is. It's not diffiuclt, and this is an ideal machien to learn
on. I can talk you right through it. I forgot to mention that I also salvaged a spare
card cage with 4 boards
in it, it's labeled "yellow card faulty", so it may be of some use.
IS this a memory box from one of the machines? If so, which one (they are
very different). If it is, the 'yellow card' is eihther the memroy data
PCB (9810) or memory addres PCB (9820). It can be repaired. If it's a
9820 memory box, it's possible that it was replaed as part of the upgrade
ot the neew RAM suystem (2102 RAMs), which would be interesting. You need
to take a very careful look t what is inside your machines.
HP part numbers for PCBs are quite helphul. THe first 5 digits are the
number of the device the board was first used in, padded with leading
seros.
And the board handls of the 9810/20 boards give the last 2 digits of the
part number using the reisstor colour code.
By fr the easiest way I've found ot treacing serious logic faults in
these machines makes use of the test connector on the CPU control PCB
(09810-66513, so brown and orange handles, it's the same in all 9800
machines). This carries the CPU mircocode address bus. Conenct a logic
analyser there and trace the microcode. Of course you need a microcode
source listing to make much sense of it...
-tony