28 Mar
2006
28 Mar
'06
10:36 a.m.
Tony wrote...
It does actually halt, right, and not hang with the Unibus in an odd
state (e.g. due to a lost grant somewhere), I trust.
Thougths (and be warned that I am not an RT11
expert)
Firstly, where does it halt?
I will get that information the next time I go down
and work on that
machine. Does anything ever appear on the
console? Is it possible there's a problem with the console interface?
Possible, but... xxdp (both v1 and v2.5) works, and vtserver (which is of
course highly dependant on the serial port) works. I've seen this sort of problem once on an
11/34. It halted when booting
RT11. It turned out that one of the DIP switches on the DL11-W console
interface card was defective, the card was therefore sending the wrong
interrupt vector. As soon as RT11 enabled interrupts on that device, it
got said bogus vector and halted (see above).
I've tried a few different
DL11-W's, all the same. I have this funny feeling
it doesn't have a good line clock.
Other oddities - the DL11-W diagnostic locks up right after it says
something like "01 devices under test" on two different DL11-W cards. On the
third card, it continues but then says something about LTC bit 7 isn't
setting. I find it hard to believe all three cards are bad... especially
when they work fine transmitting and receiving 10mb without error under
vtserver. But then, perhaps vtserver isn't doing interrupt mode.
YOu are using DL11-W cards, right? That is, ones with a built-in line
time clock. Do you have a line time clock module -- a KW11-L single-height
board -- in slot C of the very front slot of the processor backplane. If
you do, you must disable (with the DIP switches) the LTC on the DL11-W
card. If you don't then there's a wire-wrapped jumper documented
_somewhere_ in the printset that has to be in place to complete the grant
chain over the slot where the KW11-L goes.
-tony