*BSD News Article 24653


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Newsgroups: comp.os.386bsd.bugs
Path: sserve!newshost.anu.edu.au!munnari.oz.au!constellation!paladin.american.edu!europa.eng.gtefsd.com!uunet!cs.utexas.edu!utnut!nott!uotcsi2!revcan!gjk!diana!db
From: db@diana.ocunix.on.ca (Dyane Bruce)
Subject: Re: Dead com0 in NetBSD
Message-ID: <1993Dec2.004102.21003@diana.ocunix.on.ca>
Organization: db Software
References: <CHA4Iu.A5L@rucs2.sunlab.cs.runet.edu> <36094@ksr.com>
Date: Thu, 2 Dec 1993 00:41:02 GMT
Lines: 61

In article <36094@ksr.com> jfw@ksr.com (John F. Woods) writes:
>bcolbert@rucs2.sunlab.cs.runet.edu (Brad Colbert) writes:
>>   My com0 is dead!  I have tip correctly configured, I can tip com0 and
>>   I can watch the lights on my modem blink, I can even dial out, but
>>   tip doesnt display anything (the modem does have verbose and echo on).
>>   When I try to quit tip (~.) it doesnt return me to my shell, it just
>>   sits there in la-la land, I can type and it shows up on the screen but

  I had a similar problem. The standard com driver in netbsd does
not deassert DTR long enough for some modems. Including the one
I was using. The modem doesn't drop carrier, tip then hangs
when you try to exit. I haven't tracked down where the standard
NetBSD com driver sets the DTR on/off times. I am using the patched
bidirectional driver and the DTR on/off times is directly modifiable
in that driver. I just bumped up the DTR on/off times in the driver.

  But the fact you aren't getting an echo from the modem sounds
not quite the same problem.... I'd double check the cable. If the modem
lights are blinking and you are dialing out, then you have
a modem control signal problem. i.e. Your modem is not seeing
CTS or something stupid like that even though (I assume) the
MSDOS comm package works. i.e. Just the way the com driver is working
under NetBSD.


>>   no cammands are executed and nothing is sent to the modem (after trying
>>   to quit).  On a soft-reboot I selected MS-DOS as the os and tried one
>>   of my communication programs and th same thing happend.  Not till I did
>>   a hard-boot did I get moy com port back in DOS.

  I'd be curious what happens when you boot MS-DOS and power cycle
just the modem to force it to drop DCD. I hope for your sake
it isn't an infernal (internal) modem. I _hate_ those things,
for this very problem. You'd also not have a problem with
cables either. :-) Of course, you do mention the blinking lights
so it isn't right?

...

>
>Check the hardware configuration REAL HARD.  That sounds a lot like what I
>saw when I had one of my serial ports misjumpered to interrupt on the wrong
>IRQ level.

  Thats a very good possibility too. But Brad insists he got it right,
and that he "tried one of my communication programs and th
same thing happend.  Not till I did a hard-boot did I get moy com
port back in DOS. " I assume he is saying he got his com port
to work under the MS-DOS communication program he mentions after
he hard-booted his PC. 

  However, the com driver would keep kicking characters out and keep trying
to restart the SIO transmit interrupts, but no characters would ever be
received (Since RX IRQ's would get tossed). John, your guess as to what
is wrong still sounds the most likely. Perhaps Brad's MSDOS comm
package is configured backwards. Brad, what does your MSDOS (working
I assume) comm package say the COM1 IRQ level is?
-- 
Dyane Bruce				db@diana.ocunix.on.ca
29 Vanson Ave. Nepean On, K2E 6A9	So does anybody ever read
613-225-9920				what's in this space?