3 May
2021
3 May
'21
10:29 a.m.
I recently brought a PC350 back from the dead.
A good source of documentation for the F-11 is that for the 11/23 and
11/24 (e.g.,
http://bitsavers.org/pdf/dec/qbus/Digital_Microcomputer_Processor_Handbook_…
chapter 3 "LSI-11/23 Processor" or
http://bitsavers.org/pdf/dec/pdp11/1124/EK-11024-TM-001_PDP11_24_System_Tec…)
The first thing I'd do is to attach a "console terminal" cable (a cable
attached to the printer port with pin 9 pulled to ground -- pin 8).? DEC
makes such a cable called BCC08 but I just made one myself.
Then use a terminal program at 4800 to send a break and see if you get
the ODT prompt.
In my case I didn't get such a response.? It turned out that the leaky
battery had destroyed the "EPCI" at E155 (the async serial chip for the
printer/console terminal port).? I swapped the EPCI at E154 (the
keyboard async serial chip) and I was able to at least talk to the ODT.?
I then bought a replacement EPCI on eBay and I was on my way.
Good luck!
--Bjoren
On 5/3/2021 12:16 PM, Zane Healy via cctalk wrote:
On May 3, 2021, at 3:19 AM, Rob Jarratt via cctalk
<cctalk at classiccmp.org> wrote:
I have gone back to trying to fix my DEC
Professional 350. I have a printset
for the machine now. I think the CPU is being constantly reset.
Is there any documentation anywhere on the F11 chipset? Bitsavers only seems
to have the later J11.
Is the Sunsite archive still online? I seem to recall
there being some documentation there.
Zane