System V/386 3.0e (Serial Port Lockup?)

[Stu Donaldson]

Ok, I've seen reference to serial port accesses under microport
causing the port to hang.  Until now, I've ASSUMED that this was only
a problem with the AT version of Unix.

I've got a DTK 386 at 20 Mhz, and it frequently locks up when accessing
the serial port at 9600 baud.  I've not tried it at lower speeds than that,
our application is communicating with some development equipment which
we need to run 9600 baud for.  Kermit will hang after several minutes
or maybe even an hour of use.  Some software we have written here to 
talk to communicate out the port hangs almost immediately.  The only
major difference between our software and kermit, is that we are frequently
changing things with ioctl (mainly to have variable timeouts etc...)

I first thought that this was hardware, I've installed 2 ACER 1100 386
machines which work just fine in similar configurations.  Then I started
noticing some people on the net complaining about the serial ports, and
others claiming they worked for them.

We sent our hardware in to have diagnostics run on it.  They showed up
no problems whatsoever.  I'm now beginning to think it is a software (bug?)
that can't handle the slight differences in the hardware interrupt/io timings
found on the DTK machine I have.

Does anyone out there have any suggestions?  Are there any problems like
this with the other Unix's?  Interractive?  AT&T?.  I really don't want
to buy a different unix if I don't have to.  How about a freely copyable
asy.o driver to run under Microport?  Wasn't someone working on a new
driver from microport?  If so, what's the latest status?

I'm afraid I'll have to get another Unix vendor if I can't solve this
problem soon.  I've got one development station down and effectively
useless at the moment.

Thanks for any suggestions...
-- 
Stu Donaldson          UUCP: uw-beaver!uw-nsr!uw-warp!gtisqr!stu
Software Systems Mgr.  ARPA: uw-nsr!uw-warp!gtisqr!stu at beaver.cs.washington.edu
Global Technology      Bell: (206) 742-9111
Mukilteo Washington.