This isn't really a NetBSD question, but this group may know the
answer to this anyway.  I have been seeing "stray interrupt 7"
messages on my PC when I access tty02 and tty03 (PC COM3 and COM4).  I
gather that IRQ7 is what the PC interrupt controller chip generates
when it sees a glitch on an IRQ line.  I have changed the motherboard
(fearing a toasted ICU), and "both" of my 2-port COM cards (I got a
replacement, put it in as COM1/2, moved the original COM1/2 to COM3/4,
and still had the problem; put in the original COM3/4 as COM3/4 (new
card as 1/2), and it's still there.

The printer ports on the COM cards are disabled (though I haven't gone
so far as to physically cut the IRQ7 trace).  I also have an SMC
Ethernet card, an Adaptec 1542B card, and a PAS sound card (the latter
need not be present for the problem, I know that), all on the ISA bus,
plus a Cirrus Logic SVGA card on the VLB bus.

Does anyone have any experience with a similar problem, or have any
more systematic approach than to try to obtain replacements for all
the cards?  Is there a DOS program that can be used to track this down
more efficiently?  (Booting NetBSD to the point where I can type
"ttyflags -a" is a pain, plus booting NetBSD without the Adaptec is
pretty hard...)

Thanks for any help.
John Woods, jfw@funhouse.com