PDP-11/73 boot issues

[Aaron Jackson]

Hi all,

My PDP-11/73 has started misbehaving after several years of being very
stable. It is showing symptoms similar to when I've forgotten to enable
the LTC in the past, except this time, it is enable.

Power supply seems good - +5V, +12V, all seems there and appears to be
stable. I've probed the LTC going onto the backplane and I'm getting
50Hz. It looks a tad noisy, not sure if this is a problem. I will see if
I can get a picture of it, but it has very distinct rises and falls, so
hopefully that's ok. Looks to be about 50% duty cycle.

I've attempted several builds of the kernel, including the
out-of-the-box build from 2.11BSD distribution. I've also compiled a
shrunk down kernel without a bunch of devices I don't have, but it still
fails to work. I am using a SCSI2SD so it's easy for me to copy images
and test them in SIMH - they all boot fine in SIMH with a similar setup
(mscp, tmscp, 11/73, 1MB-ish RAM).

Does anyone have any ideas what might be causing this? I've run out of
ideas unfortunately. I'll stick a dump of the boot below, with debug
flag passed showing output from autoconfig.

I've also tried it without the tmscp card - just CPU, RAM and Emulex
UC07 in MSCP mode for scsi disk. I have tried it with less memory, and
I've tried removing the halt jumper from the 11/73 board (W5 if I
remember correctly)

Cheers,
Aaron

---------
^C
BOOT>  DU 0

73Boot from ra(0,0,0) at 0172150
: ra(0,0,0)unix -D
Boot: bootdev=02400 bootcsr=0172150

2.11 BSD UNIX #116: Wed Dec 31 18:01:57 CST 1969 
    root at localhost.2bsd.com:/usr/src/sys/GENERIC

ra0: Ver 5 mod 13
ra0: RA81  size=1216601

phys mem  = 1179648
avail mem = 959040
user mem  = 307200


_hkprobe = 0
_hkattach = 143330
_hkVec = 0
hkintr = 120
_htprobe = 0
_htattach = 143550
_htVec = 0
htintr = 150
_raprobe = 0
_raattach = 34270
_raVec = 34200
raintr = 100
_rkprobe = 0
_rkattach = 144650
_rkVec = 0
rkintr = 130
_rlprobe = 0
_rlattach = 144770
_rlVec = 0
rlintr = 110
_tmprobe = 0
_tmattach = 143610
_tmVec = 0
tmintr = 160
_tmsprobe = 0
_tmsattach = 143740
_tmsVec = 143730
tmsintr = 200
_tsprobe = 0
_tsattach = 143660
_tsVec = 0
tsintr = 170
_xpprobe = 0
_xpattach = 0
_xpVec = 0
xpintr = 0
endvec = 1000
_conf_int = 16124
CGOOD = 14
CBAD = 24
_nextiv = 5500
trap = 4150
_version = 17400
KERN_NONSEP = 0
Grab 177440 = 36556hk ? csr 177440 vector 210 skipped:  No CSR.
Grab 172440 = 36556ht ? csr 172440 vector 224 skipped:  No CSR.
Grab 172150 = 0Grab 156 = 240Grab 154 = 100Stuff 14 @ 154
Stuff 340 @ 156
probe ra: return conf_int:Stuff 100 @ 154
Stuff 240 @ 156
ra ? csr 172150 vector 154 bad probe value 224.
Grab 177400 = 36556rk ? csr 177400 vector 220 skipped:  No CSR.
Grab 174400 = 36556rl ? csr 174400 vector 160 skipped:  No CSR.
Grab 172520 = 36556tm ? csr 172520 vector 224 skipped:  No CSR.
Grab 174500 = 0Grab 262 = 0Grab 260 = 0tms ? csr 174500 vector 260 interrupt vector already in use.
Grab 172520 = 36556ts ? csr 172520 vector 224 skipped:  No CSR.
xp ? csr 176700 vector 254 skipped:  No autoconfig routines.


At this point it is stuck no matter how long I wait.