I put the string "sun serial cable" into Google and the first link in the list
had a diagram.
http://www.stokely.com/unix.serial.port.resources/A-B-Ycablepinout.html
If your serial port is bad (rare, but I've seen it happen) and your video card is
bad, you've got to get one of them fixed. If you're not experienced enough to
know whether this is the case you ought to get someone who is. There is a
learning curve with Sun hardware and without taking classes, or having a mentor
handy or a lab to play with that curve can be pretty steep.
I think you'd have to do something really radical to the OBP to not get any video
at all, although the bigger machines (E4500, and so on) won't give you any video
for a long time if you have diagnostics set to max.
> I can't find a pin diagram for null modem cables. What other pin
> connections do I need or is it just these two?
> Is there anything special I need to do in order to get output to appear?
> So far I've had no luck.
> > Sorry - I should have been more explicit. You will need a null modem cable
> > between your PC and the Sun Serial A port.
> > On the DB25 tx=pin2, rx=pin3 (Sun serial)
> > On the DB9 tx=pin3, rx=pin2 (PC serial)
> >>I pulled the machine out of the server room and it's currently sitting
> >>on my desk. I've plugged a serial cable (taken from a modem) from the 25
> >>pin labelled 'A' to my (9 pin) serial port.
> >>Running minicom (on Linux) produces no video, I've disconnected the
> >>keyboard and monitor on the Ultra and cycled the power.
> >>My terminal setting should be 8N1, 9600 right?
> >>A previous post mentioned hitting Ctrl-Break from a terminal session to
> >>get the A prompt, but that doesn't seem to work either...
> >>What next?!
> >>>Most Sun hardware looks for the existence of a keyboard at boot time. If
> >>>it doesn't see a keyboard it will direct the keyboard/video functions to
> >>>Serial A (called "headless" operation). Plug a terminal into Serial A or a
> >>>serial cable to your laptop and you will find your lost video.
> >>>>Running an Sun Ultra Enterprise 2 with Solaris 8 installed.
> >>>>This was working fine with keyboard connected, but when I tried
> >>>>booting without there was no repsonse via network; so I assume it does
> >>>>not boot properly.
> >>>>I tried forcing (via the SET-ENV command in NVRAM) to make the input
> >>>>device ttya and output device ttya but still no joy. Of course now I
> >>>>can't access the NVRAM or do anything because I/O is redirected
> >>>>(couldn't access via serial either).
> >>>>So I followed the advice of previous posts and hit STOP-N to revert to
> >>>>defaults.
> >>>>This appears to have actually worked, the monitor makes a convincing
> >>>>clicking sound and keyboard lights flash when started, however nothing
> >>>>ever appears although I can toggle caps lock so it is obviously
> >>>>responding.
> >>>>Any suggestions?
> >>>>Thanks muchly
> >>--
> >>Jonathon Horsman
> >>Systems Administrator - Jungle Drum
> >>Ph: 09 3744510
> >>Mob: 021 322595
> --
> Jonathon Horsman
> Systems Administrator - Jungle Drum
> Ph: 09 3744510
> Mob: 021 322595
by