27 May
2008
27 May
'08
9:37 p.m.
Hi,
Has anyone have or know where to get an IBM XT (5160) diagnostic ROM? I am
trying to revive an original IBM XT motherboard which is nonresponsive and
gives no error codes (beep or POST).
I am not even sure such a ROM exists but it would be a 27C256 style EPROM
that plugs into an IBM XT motherboard to help fault isolate an almost
completely dead unit.
The motherboard CPU seems to be working based on a quick exam with the
oscilloscope. However, the motherboard's initialization / boot process is
not making it to start up the video display before it hangs or crashes.
Obviously, something is broken but I haven't isolated exactly what yet.
If anyone can help, I would much appreciate it. Thank you in advance.
Andrew Lynch
27 May
27 May
11:05 p.m.
On Tue, 27 May 2008, Andrew Lynch wrote:
Has anyone have or know where to get an IBM XT (5160)
diagnostic ROM? I am
trying to revive an original IBM XT motherboard which is nonresponsive and
gives no error codes (beep or POST).
I am not even sure such a ROM exists but it would be a 27C256 style EPROM
that plugs into an IBM XT motherboard to help fault isolate an almost
completely dead unit.
It DID exist. Todd Fischer? made a diagnostic ROM. It came with a serial
board, and required that you supply a terminal. The chances of my finding
mine are zilch. Unlike a POST card, it could diagnose a dead CPU, etc.
If anyone can help, I would much appreciate it. Thank
you in advance.
I don't think that it is much help to tell you of the existence of
something unobtainable.
11:54 p.m.
On Tuesday 27 May 2008 23:05, Fred Cisin wrote:
On Tue, 27 May 2008, Andrew Lynch wrote:
How the heck is a diagnostic ROM going to diagnose a dead CPU? I must be
missing something here...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
Has anyone have or know where to get an IBM XT
(5160) diagnostic ROM? I
am trying to revive an original IBM XT motherboard which is nonresponsive
and gives no error codes (beep or POST).
I am not even sure such a ROM exists but it would be a 27C256 style EPROM
that plugs into an IBM XT motherboard to help fault isolate an almost
completely dead unit.
It DID exist. Todd Fischer? made a diagnostic ROM. It came with a serial
board, and required that you supply a terminal. The chances of my finding
mine are zilch. Unlike a POST card, it could diagnose a dead CPU, etc. 
8:58 a.m.
> How the heck is a diagnostic ROM going to diagnose
a dead CPU? I
> must be missing something here...
Well, if it's a little more than just ROM but fits in a ROM socket, it
could, for example, notice a lack of read cycles. If it's enough more
than ROM it could run a CPU emulator and notice that it isn't obeying
the instructions it's fetching (though that's hard to do right, since
the ROM socket doesn't see things like interrupts or RAM).
/~\ The ASCII der Mouse
\ / Ribbon Campaign
X Against HTML mouse at rodents.montreal.qc.ca
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
2:37 p.m.
>> How the heck is a diagnostic ROM going to
diagnose a dead CPU? I
>> must be missing something here...
Yeah, I've said some stupid things on this list, and yesterday's was
record breaking.
On Wed, 28 May 2008, der Mouse wrote:
Well, if it's a little more than just ROM but fits
in a ROM socket, it
could, for example, notice a lack of read cycles. If it's enough more
than ROM it could run a CPU emulator and notice that it isn't obeying
the instructions it's fetching (though that's hard to do right, since
the ROM socket doesn't see things like interrupts or RAM).
Fischer's setup was just a ROM (EPROM?), plus he had a serial board that
was hardware configured for 9600, so that it would not be dependent on the
initialization code to setup the port.
Now, if you had a setup that connected to the bus, to the ROM sockets, to
the RAM sockets, and had a CPU plus connection to the 8088 and 8087
sockets, . . .
There was once a POST card that did CLAIM to test everything, in true
marketing form: "Power lights good, no Power On Self Test codes = "Bad
CPU", replace motherboard". Tony would be happy to know that they didn't
stay in business very long.
--
Grumpy Ol' Fred cisin at xenosoft.com
12:39 a.m.
On Wednesday 28 May 2008 00:08, Eric Smith wrote:
Roy wrote:
African or European?
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
How the heck is a diagnostic ROM going to
diagnose a dead CPU? I must be
missing something here...
I wondered that too. maybe it's not dead, just pinin' for the fjords. 
3:10 a.m.
Andrew,
I have one, it's not IBM but third-party.
We used it to test XT's, I'll make you a image.
It is 64k but I'll check if it's readable.
And I should have the manual some where, but it's a very simple user
interface.
And it's does test the hardware.
Rik
-----Oorspronkelijk bericht-----
Van: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org]
Namens Andrew Lynch
Verzonden: woensdag 28 mei 2008 3:37
Aan: cctalk at classiccmp.org
Onderwerp: IBM XT diagnostic ROM
Hi,
Has anyone have or know where to get an IBM XT (5160) diagnostic ROM? I am
trying to revive an original IBM XT motherboard which is nonresponsive and
gives no error codes (beep or POST).
I am not even sure such a ROM exists but it would be a 27C256 style EPROM
that plugs into an IBM XT motherboard to help fault isolate an almost
completely dead unit.
The motherboard CPU seems to be working based on a quick exam with the
oscilloscope. However, the motherboard's initialization / boot process is
not making it to start up the video display before it hangs or crashes.
Obviously, something is broken but I haven't isolated exactly what yet.
If anyone can help, I would much appreciate it. Thank you in advance.
Andrew Lynch
5894
days inactive
5894
days old
8 comments
6 participants
participants (6)
-
cisin＠xenosoft.com -
dr.emiel＠xs4all.nl -
eric＠brouhaha.com -
lynchaj＠yahoo.com -
mouse＠Rodents.Montreal.QC.CA -
rtellason＠verizon.net