On 11/22/16 5:13 PM, Guy Sotomayor Jr wrote:
On Nov 22, 2016, at 4:40 PM, Josh Dersch <[email protected]> wrote:
So... maybe I just completely missed the memo on this, and maybe there's still
something wrong with my backplane... is it possible that slot 9 of the 11/40's
CPU backplane is wired *specifically* for an M7800? I guess I need to spend
some time tonight seeing what the differences are... but now I need to go
attend to a cranky 2yo who just woke up from a nap…
I seem to recall something similar with one of the 11/40’s I was working on. I
believe that because the 11/40 CPU backplane is wired for an M787 that things
don’t work quite right if you try and install an M7856 into the SPC slot in the
backplane and try and use it and not the M787. There is a way to jumper the
CPU backplane so you can use na M7856 and not the M787. I haven’t really
investigated it in detail (and it’s been a long time since I messed around with
the 11/40 at that level).
TTFN - Guy
Interesting. I suppose the LTC on the M7856 could also be disabled...
I'll have to try that and see if it works. The DL11-W manual doesn't
seem to cover any special installation procedures for the 11/40, and the
11/40 System Manual describes Slot 9 as a "SMALL PERIPHERAL CONTROLLER
(USUALLY DL11)" slot without mentioning the lack of NPG and the LTC
oddity. Weird.
I now have the CPU passing diagnostics with flying colors (there was a
problem with the IR Decode logic causing incorrect reserved instruction
traps), and I can boot RT-11 from the SCSI controller, yay. Now to
track down the EIS and Stack Limit options...
- Josh
