YASPP (Yet another serial port problem)

[martin.j.shannon]

In article <10740 at attctc.Dallas.TX.US> cassidy at attctc.Dallas.TX.US (Cassidy Lynar) writes:
>Hi, I am having problems *still* trying to bring up a third serial port
>on my system.

[What looks like a good set of sdevice entries]

>Now as for the third I/O board, (I forget the make) it has jumpers that
>allow to PHYSICALLY change the addresses from 3f8 to 3e8 and the irq from
>4 to 5.

Sounds like the right thing to do.

>I also tried to as ISC put it, "fake the kconfig" and modified the
>/etc/conf/pack.d/space.c and changed the entry to:
>	ASY_3_SIOA+6,	/* foo..... */
>	ASY_5_VECT,	/* more foo */
>and rebuilt the kernel (this is the second time, the first attempt was
>not using a modifed space.c.

Yeah, that oughtta work, too, I think.

>Ok, here is the actual problem, the kernel builds fine, getty spawns
>fine, but the probs are 1) the getty process becomes a non-killable process
>			2) when I cat foo >> /dev/tty02, the terminal on the
>other end, receives the data at a smoking 1 cps or less.

That's a symptom I recognize: the ASY driver is not getting interrupts
from that card.  The only reason you get any output at all is the 1-second
sanity timer used to deal with missed interrupts on heavily loaded machines.

>I know that the
>terminal is fine, as I used it at work before bringing it home, and I also
>know that the card and modems do not conflict, as I have no troubles at all
>when I boot a DOS communications package, and use a modem on the third port.

Yeah, well, DOS doesn't use interrupts for the COM devices, so the fact that
a serial port runs under DOS *DOES* *NOT* mean you have it configured properly
for UNIX (ISC or any other brand of System V Release 3+ on the '386).

[Some pissing & moaning (not entirely unwarranted) deleted.]

>							Cassidy Lynar

Bottom line: your jumpers on the ASY port 2 don't match what the driver
thinks is the correct interrupt.  You may have a conflict with another
interrupt device, or either the ASY's space.c or your jumper may be wrong.
The bugs (that *I* have heard of) in ISC's ASY driver don't involve any
missed interrupts (except at very high speeds on loaded machines).
-- 
Marty Shannon; AT&T Bell Labs; Liberty Corner, NJ, USA
(Affiliation is given for identification only:
I don't speak for them; they don't speak for me.)