23 Feb
2018
23 Feb
'18
5:10 a.m.
Well, I bought that DEC Pro 350 on ebay. It initially booted up and I got
the error screen. The error code I found on the Internet was related to
the hard disk controller. So, I thought I just needed someone to sell/give
me some systems disks for the unit and I could try to setup the drive again
if it still functioned.
Then, it after a couple of restarts (I re-seated the boards and cleaned the
connectors) it stopped showing the error screen (with picture of the
computer). All the diagnostic lights are red on the back and nothing ever
shows on the screen. The power comes on and then nothing.
If anyone has any thoughts, I would appreciate it. I knew the history of
this type of computer and figured it was a long shot. I am just
disappointed to have gotten really nowhere with it.
Thanks!
Kurt
25 Feb
25 Feb
11:42 a.m.
On Fri, Feb 23, 2018 at 8:10 AM, Kurt Hamm via cctalk <cctalk at classiccmp.org
wrote:
Well, I bought that DEC Pro 350 on ebay. It initially
booted up and I got
the error screen. The error code I found on the Internet was related to
the hard disk controller. So, I thought I just needed someone to sell/give
me some systems disks for the unit and I could try to setup the drive again
if it still functioned.
Then, it after a couple of restarts (I re-seated the boards and cleaned the
connectors) it stopped showing the error screen (with picture of the
computer). All the diagnostic lights are red on the back and nothing ever
shows on the screen. The power comes on and then nothing.
If anyone has any thoughts, I would appreciate it. I knew the history of
this type of computer and figured it was a long shot. I am just
disappointed to have gotten really nowhere with it.
Thanks!
Kurt
Kurt,
Sounds like you can't do much of anything but to confirm my understanding...
Can you enter terminal mode?
Can you boot from a diskette?
How confident are you in the power supply? Have you checked all of the
voltage rails?
Bill
12:17 p.m.
fredag 23 februari 2018 skrev Kurt Hamm via cctalk <cctalk at classiccmp.org>:
Well, I bought that DEC Pro 350 on ebay. It initially
booted up and I got
the error screen. The error code I found on the Internet was related to
the hard disk controller. So, I thought I just needed someone to sell/give
me some systems disks for the unit and I could try to setup the drive again
if it still functioned.
Then, it after a couple of restarts (I re-seated the boards and cleaned the
connectors) it stopped showing the error screen (with picture of the
computer). All the diagnostic lights are red on the back and nothing ever
shows on the screen. The power comes on and then nothing.
The tech manual is :
http://bitsavers.informatik.uni-stuttgart.de/pdf/dec/pdp11/pro3xx/EK-PC350-…
In case you haven't already found it.
All LED on means sytem module failed. (Page 5-33). Have you checked power
supply voltages? I would try to remove all option boards and see if that
makes any difference. The printer port is actually a console port. The
details is in the manual (page 5-126 and 5-131). I suspect that all leds
come on if it fails to run the rom based diagnostic. It might have halted
to uODT in case you could try use the console to see if you could diagnose
the problem.
If anyone has any thoughts, I would appreciate it. I
knew the history of
this type of computer and figured it was a long shot. I am just
disappointed to have gotten really nowhere with it.
Thanks!
Kurt
Good luck!
/Mattis
2:39 p.m.
Thanks for the suggestions. Interestingly, upon first boot I was able to
get the hard disk controller error with the picture of the computer. Then,
sure subsequent reboots failed to display anything.
I removed all the cards and booted with no luck.
It looks like I will need to build a cable to try terminal mode. I did
hook a vt220 with a 9to25 cablw, but didn't get anything.
Since successful booting is intermittent, probably a heat or power
problem. I will continue to try to get terminal mode working.
Kurt
On Feb 25, 2018 3:17 PM, "Mattis Lind" <mattislind at gmail.com> wrote:
fredag 23 februari 2018 skrev Kurt Hamm via cctalk <cctalk at classiccmp.org
:
Well, I bought that DEC Pro 350 on ebay. It
initially booted up and I got
the error screen. The error code I found on the Internet was related to
the hard disk controller. So, I thought I just needed someone to
sell/give
me some systems disks for the unit and I could try to setup the drive
again
if it still functioned.
Then, it after a couple of restarts (I re-seated the boards and cleaned
the
connectors) it stopped showing the error screen (with picture of the
computer). All the diagnostic lights are red on the back and nothing ever
shows on the screen. The power comes on and then nothing.
The tech manual is : http://bitsavers.informatik.
uni-stuttgart.de/pdf/dec/pdp11/pro3xx/EK-PC350-TM-001_
Professional_300_Series_Technical_Manual_Dec82.pdf
In case you haven't already found it.
All LED on means sytem module failed. (Page 5-33). Have you checked power
supply voltages? I would try to remove all option boards and see if that
makes any difference. The printer port is actually a console port. The
details is in the manual (page 5-126 and 5-131). I suspect that all leds
come on if it fails to run the rom based diagnostic. It might have halted
to uODT in case you could try use the console to see if you could diagnose
the problem.
If anyone has any thoughts, I would appreciate
it. I knew the history of
this type of computer and figured it was a long shot. I am just
disappointed to have gotten really nowhere with it.
Thanks!
Kurt
Good luck!
/Mattis
26 Feb
26 Feb
6:23 a.m.
On Feb 25, 2018, at 5:39 PM, Kurt Hamm via cctalk
<cctalk at classiccmp.org> wrote:
Thanks for the suggestions. Interestingly, upon first boot I was able to
get the hard disk controller error with the picture of the computer. Then,
sure subsequent reboots failed to display anything.
I removed all the cards and booted with no luck.
That would be the expected result if the status lights indicate a motherboard failure --
it means you're not reaching the point where it looks at the I/O cards.
It looks like I will need to build a cable to try
terminal mode. I did
hook a vt220 with a 9to25 cablw, but didn't get anything.
You need a cable specifically wired as console cable. Check the technical manual for the
details. The DB25 connector is used to connect either a (serial) printer or a console,
and the two are distinguished by a jumper between two of the pins. So a console cable has
that jumper in its connector, a printer cable does not. If you don't have the jumper,
the speed will be set differently (4800 rather than 9600) and the UART will not appear at
the console UART address.
paul
11:56 a.m.
Yeah, the fact that the issue is intermittent (mostly not booting) is
weird.
Just to be clear, You mentioned a 25 pin connector. My understanding is
that the console port is the printer port which is a 9 pin connector.
Thanks for the info. I have ordered the stuff to make a cable so should be
able to test console port this weekend.
Kurt
On Mon, Feb 26, 2018 at 9:23 AM, Paul Koning <paulkoning at comcast.net> wrote:
On Feb 25, 2018, at 5:39 PM, Kurt Hamm via cctalk
<cctalk at classiccmp.org>
wrote:
Thanks for the suggestions. Interestingly, upon first boot I was able to
get the hard disk controller error with the picture of the computer.
Then,
sure subsequent reboots failed to display
anything.
I removed all the cards and booted with no luck.
That would be the expected result if the status lights indicate a
motherboard failure -- it means you're not reaching the point where it
looks at the I/O cards.
It looks like I will need to build a cable to try
terminal mode. I did
hook a vt220 with a 9to25 cablw, but didn't get anything.
You need a cable specifically wired as console cable. Check the technical
manual for the details. The DB25 connector is used to connect either a
(serial) printer or a console, and the two are distinguished by a jumper
between two of the pins. So a console cable has that jumper in its
connector, a printer cable does not. If you don't have the jumper, the
speed will be set differently (4800 rather than 9600) and the UART will not
appear at the console UART address.
paul
12:27 p.m.
On Feb 26, 2018, at 2:56 PM, Kurt Hamm <kurt at
hamm.me> wrote:
Yeah, the fact that the issue is intermittent (mostly not booting) is weird.
Just to be clear, You mentioned a 25 pin connector. My understanding is that the
console port is the printer port which is a 9 pin connector.
Sorry, you're right, my bad memory. The DB25 is at the other end of the standard DEC
cables, of course.
The relevant documentation is table 5-26, page 181 (5-131) of the PRO technical manual,
volume 1. "Terminal L" (pin 9) is the signal that says "this is a console
terminal" -- jumper that to signal ground (pin 7). That is also stated explicitly on
page 177 (5-127), third paragraph.
paul
2449
days inactive
2452
days old
6 comments
4 participants
participants (4)
-
billdegnan＠gmail.com -
kurt＠hamm.me -
mattislind＠gmail.com -
paulkoning＠comcast.net