RE: PM2 disconnecting sessions

Barry Hemphill (ubu@easynet.on.ca)
Fri, 17 Jan 1997 06:00:15 +5

I've seen a number of postings on this subject, and I've yet to see
anyone mention IRQ conflicts, which I find cause about 80% of
disconnect problems, particularly since it's become so common to
assemble new systems with built in conflicts. Ask your customer what
com port their modem is on - if it isn't on 1 or 2, theres at least
an even odds chance they have a conflict. A few notes:

- If they have com1 and 2 on the motherboard (or I/O card), and an
internal modem on either com3 or 4, odds are the modem is sharing an
IRQ with an existing com port, and *very* few systems can do this
reliably. Also note, it is *still* a conflict even if nothing is
using the conflicting port, ie there is nothing plugged into com2
(but it is still enabled), and the modem is on com4, where both are
on IRQ3 - that is a conflict, and will cause problems in the majority
of systems.

- If the modem is on com4, it may have a base address conflict with
the video card - com4 uses address 2E8-2EF, which is also used by
many video cards. It's hard to spot this conflict, but if you move it
and the problem disappears...

- In general, if the system has more than 2 com ports, lose one.
Really, there are basically only two serial devices left - mice and
modems (well, a few other obscure ones). Why would you want to have
that third com port? If you stick with the mouse on com1 (unless of
course it's PS/2) and modem on com2, with no com3 or com4, your odds
of having a conflict are pretty slim.

Just thought I'd toss these in, as the above have reliably eliminated
disconnect problems for hundreds of my users. They might just help
yours out too.

Barry

Barry Hemphill EasyNet Inc.
System Administrator Cambridge, Ontario, Canada
ubu@easynet.on.ca (519)654-9999 fax(519)654-0301

The typical Nintendo game involves controlling a little man running
around a maze while numerous powerful and inexplicably hostile forces
try to destroy him. In other words, it's exactly like real life.
-- Dave Barry