[rescue] RS6k serial console tips?

[Sheldon T. Hall]

 Todd Carson writes ...
[snip]
> I was hoping people with more experience with
> RS/6000 hardware and AIX might have an idea of what's going on.

That would not be me, but ...

> Since I don't have the right cable to connect the RS/6000 to my
> U10 sitting right beneath it, I'm using a Mac Classic with
> Kermit. They're connected with a Sun-branded DB-25 to MiniDIN-8
> cable ande a Radio Shack "null modem adapter".

Not all cables like that are created equal.  I use a "Mac Plus Modem Cable"
and a null modem adapter to talk to a Sun IPX or an SGI Indigo2, using a PC
laptop.  No problem.

I have a "Mac Printer Cable" which is also mini-DIN to DB-25, and you'd
think you could use that, but you can't, either with or without a null
modem.

> I'm assuming the
> cable and terminal settings (9600 8N1, DTR handshaking) are okay
> since I was able to use the kernel debugger. Maybe this is a bad
> assumption to make, I don't know.

I'd try it without any handshaking.  Not just everyone has the same ideas
about that, and the cable or adapter may hose it up, anyway.  9600 isn't all
that fast, so you ought to be able to get along without the handshaking.

Back when serial comms was The Thing, I'd often end up using just three
wires (2, 3, and 7 on a DB-25), to avoid odd handshaking problems.

-Shel