27 Mar
1999
27 Mar
'99
3:05 a.m.
Hello, all:
While looking at the new JDR Microdevices catalog, a few items jumped
out:
1. S100 bus connectors #100P-WW $1.99
2. AppleBus connectors #50P-WW $2.99
3. CBM/KIM/AIM #44P-WW $0.99
4. Intel 8272 FDC $0.99
5. CTS256AL2 (text-to-speech) $4.99
6. 1793 FDC $7.99
7. TMS99532 (modem chip) $3.99
[ Rich Cini/WUGNET
[ ClubWin!/CW7
[ MCP Windows 95/Windows Networking
[ Collector of "classic" computers
[ http://highgate.comm.sfu.ca/~rcini/classiccmp/
[ http://highgate.comm.sfu.ca/~rcini/pdp11/
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15 May
15 May
8:24 a.m.
New subject: Northstar Assistance Request
Greetings,
I pulled the Northstar Horizon out of storage now that I have time
to take another crack at restoring it. It has an MDS-A3 controller,
which I connected to an MPI-52 full-height 5.25" drive. When I boot
it, I can hear it jiggle the heads a few times (a good sign generally)
but then it just spins the disk for a minute (I can't hear the heads
moving) and then stops.
I've used disks in it sent to be my Doug Coward and by Don Maslin
(Don, I put some money in an envelope to mail to you on monday!)
and both exhibit the same behavior.
Are there any reasons I shouldn't use an MPI-52 with the MDS-A3?
Could the jumpers on the MPI-52 be set incorrectly to act as a
single drive in this system?
What other sorts of problems will cause this sort of behavior
on this particular machine?
At no point is anything displayed on the terminal. I've verified
the baud rate at 9600 and tried with hardware handshaking on and off.
I've also tried both serial ports as an experiment. At any rate,
I don't think serial comm is the problem here since it's my understanding
that the N* will only display terminal messages IF it successfully loads
an OS and I just don't hear those heads moving around doing reads.
In either case, I ASSUME that the terminal needs to be plugged into
the RIGHT serial connector, closest to the parallel ports. I put a
breakout box on it and it says all the lines are happy.
Thoughts? Suggestions? Ideas? Speculations?
Thanks...
Anthony Clifton
16 May
16 May
12:16 p.m.
New subject: Northstar Update
OK, I ran through the Integrated Systems tests in the Northstar
Horizon Computer System manual and I've discovered a few things.
1. I don't think it's the floppy drive or the controller or the
disks. According to the steps that I completed successfully, the
problem is most likely with the RAM conflicting with the PROM
address on the MDS-A3 disk controller.
2. I pulled ALL the RAM out of the machine, as per the instructions,
and put just the RAM A3 (16k N* card) into the machine for testing.
BUT, after testing, I pulled it out and found one of the bypass caps
is broken off at the board surface (easy fix).
QUESTIONS:
I can repair the RAM 16 A3 but I don't have the switch settings and
jumper settings (J) to set it to start at 2000H. What are these?
Also, I have a RAM 16 A2 board that I can try. Are the switch settings
and the jumper settings on it the same as the A3 to start at location
2000H?
Finally, will NSDOS run in 16K ram? I see no indication in the manuals
that it won't but it's a good question to ask anyway.
Thanks...
Anthony Clifton
I pulled the Northstar Horizon out of storage now that
I have time
to take another crack at restoring it. It has an MDS-A3 controller,
which I connected to an MPI-52 full-height 5.25" drive. When I boot
it, I can hear it jiggle the heads a few times (a good sign generally)
but then it just spins the disk for a minute (I can't hear the heads
moving) and then stops.
9354
days inactive
9404
days old
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