25 Oct
2012
25 Oct
'12
2:12 p.m.
On Wed, 24 Oct 2012, Kevin Reynolds wrote:
I have been trying to get a microvax II fully
functional over the last
few weeks and I seem to have a roadblock. The system used to boot and
allow logins, but now after connecting a VCB-02 cable to display,
keyboard and mouse, it has become more and more unreliable.
At first when connected to a display the system would
kernel panic
during boot. It would boot WITHOUT the display being connected,
however, so I continued using it without the display. Unfortunately,
now it appears to panic every boot, and I can't get to a prompt to run
any diagnostics such as anal/crash. No user based changes were made to
the system between boots. The real brain teaser is that it doesn't
always crash during the same process load, I have been trying to get a
microvax II fully functional over the last few weeks and I seem to have
a roadblock. The system used to boot and allow logins, but now after
connecting a VCB-02 cable to display, keyboard and mouse, it has become
more and more unreliable. The real brain teaser is that it doesn't
always crash during the same process load, sometimes its OPCOM,
sometimes its STARTUP, sometimes its DECW$STARTUP as it is below.
Anyone have any insight on how to proceed? I'm not a very experienced
user. A crash example is below:
If you haven't already, check the outputs of the power supply with an
oscilloscope. This is exactly what my BA123 MicroVAX II / MicroVAX III
(tried different board sets) did and it turned out to have very bad ripple
on the outputs. I'm fairly certain my BA123's power supply has bad
electrolytics, but unfortunately I don't have a list of parts because I've
not yet rebuilt it. At the time I didn't have room on the bench to tear it
down so I put the project aside and I've not yet gotten back to it.