[ On Tue, November 10, 1998 at 12:43:02 (-0500), Todd Vierling wrote: ]
> Subject: SS2 drops DTR when ttya as console inits?
>
> I haven't really noticed it before, as my SS2 console used to be a terminal.
> But now that it's a `cu' connected null modem cable, I've noticed that DTR
> seems to drop for a moment when the ttya (zstty0) initializes in the dmesg.
> `cu' sees a hangup signal immediately after the messages:
> 
> zs0 at mainbus0 ioaddr 0xf1000000 ipl 12 softpri 6
> zstty0 at zs0 channel 0 (console)
> 
> This is in latest -current.  Has it always been like this?  Can it be
> avoided?

I don't think the OS has anything to do or say about it.

It's been that way since at least way back in the early Sun-3 PROMs and
indeed most systems I've run with "proper" serial consoles work this
way.  (Most of the terminal's I've used do have a DTR indicator.)  In
fact I'd be perturbed by any system which did not do this.

If you're using another computer as a terminal "server", then you'll
probably want to reduce the console's RS-232 signaling to the basic
2+3+7 and tie back 6+8+20 on both ends.  This'll prevent hangups by cu
when you reboot the target system (or it crashes and reboots itself! ;-).

-- 
							Greg A. Woods

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