28 Jun
2016
28 Jun
'16
9:33 a.m.
So, after finding that a DL11-E wasn't working in the backplane SPC
slots (26-28) on my 11/45, I took a closer look. The problem isn't
exactly what I had expected -- -15V seems to be distributed there, but
+15 is not.
Looking closely at the print sets, the listed configurations only
mention DL11-A, the 20ma current loop model, which wouldn't require +15
to work. I wonder if some +15 distribution wires were added in an ECO,
or maybe EIA console from the backplane SPC slots was never supported
for these early 11/45s (mine is serial 152).
There's one other oddity -- the power distribution table in
EK-11045-MM-007, page 510, implies that +15 should be distributed to the
SPC slots on CA1. I'm wondering if this is a typo, since I'd expect
that pin to be NPG? The DL11-E looks to be expecting +15 on UA1 in any
case.
28 Jun
28 Jun
11:52 a.m.
On 06/28/2016 09:33 AM, Fritz Mueller wrote:
...the power distribution table in EK-11045-MM-007,
page 510, implies
that +15 should be distributed to the SPC slots on CA1. I'm wondering
if this is a typo, since I'd expect that pin to be NPG? The DL11-E
looks to be expecting +15 on UA1 in any case.
(Typo'd that last sentence -- should say "CU1").
11:55 a.m.
DD11A or B would have power to CA1 unless you remove the wirewrap, right?
On Tue, Jun 28, 2016 at 2:52 PM, Fritz Mueller <fritzm at fritzm.org> wrote:
On 06/28/2016 09:33 AM, Fritz Mueller wrote:
--
@ BillDeg:
Web: vintagecomputer.net
Twitter: @billdeg <https://twitter.com/billdeg>
Youtube: @billdeg <https://www.youtube.com/user/billdeg>
Unauthorized Bio <http://www.vintagecomputer.net/readme.cfm>
...the power distribution table in
EK-11045-MM-007, page 510, implies
that +15 should be distributed to the SPC slots on CA1. I'm wondering if
this is a typo, since I'd expect that pin to be NPG? The DL11-E looks to be
expecting +15 on UA1 in any case.
(Typo'd that last sentence -- should say "CU1").
12:36 p.m.
On 06/28/2016 11:55 AM, william degnan wrote:
DD11A or B would have power to CA1 unless you remove
the wirewrap, right?
The way the prints look to me, the DD11A and B take +5V on CA2, DA2,
EA2, FA2, which is per normal for SPC slots that I've seen. I can't
find reference to CA1 in the DD11 prints, and indeed looking at the
several DD11 cards that I have on hand the CA1 pad is not connected to
any traces.
Also, all the SPC pinouts I've seen list CA1 and CB1 as the NPG chain.
So it would be weird/wrong to have power there? So I'm suspecting this
is a typo in the 11/45 maint manual.
I'd be interested to know from anybody else out there who has a running
11/45 or 55, do you have +15V on slots 26-28 CU1? What about slots
26-28 CA1?
--FritzM.
3 Jul
3 Jul
12:04 p.m.
Just a follow-up here: Marty over at vcfed.org took a look at his
11/45, and he does have +15 (+12 in his case) to CU1 on slots 26-28.
His notes indicate a wire from slot 15 (because of his setup he can't
conveniently inspect his backplane). It's
not clear whether this is from factory, and ECO, or a user mod.
Marty's machine does not have power to CA1 either, so it really does
look like this is a typo in the DEC docs.
2863
days inactive
2868
days old
6 comments
2 participants
participants (2)
-
billdegnan＠gmail.com -
fritzm＠fritzm.org