Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!cs.utexas.edu!ico!vail!rcd
From: rcd@ico.ISC.COM (Dick Dunn)
Newsgroups: comp.unix.i386
Subject: Re: Ethernet boards for ISC 386/ix
Summary: IRQ2 is already used
Message-ID: <16013@vail.ICO.ISC.COM>
Date: 16 Aug 89 16:04:30 GMT
References: <1423@hydra.gatech.EDU> <[140.1]comp.unix.i386;1@point.UUCP>
Organization: Interactive Systems Corp, Boulder, CO
Lines: 18

> >...board will support IRQ 2.  Thus, I edited the sysadm script to allow
> >me to set an IRQ of 2 (and of course set the board likewise)...
>...Ya gotta watch that 'assuming' stuff!  IRQ2 may well be your problem.  I've
> had a number of problems with IRQ2 under ISC 2.01.  Come to think of it, I
> haven't gotten *anything* to work on IRQ2 since I upgraded from 1.0.6...

In a strict sense, you can't use IRQ2, period.  IRQ2 is the line for the
second interrupt controller on an AT.  That is, there are two interrupt
controllers in the machine, but they're cascaded.  One can yank directly on
the 386 interrupt-request; the other yanks on an interrupt line of the
first.

Some of the old configuration code may have treated IRQ2 as if you'd said
IRQ9--that is, it may have bypatched the attempt to put a device on IRQ2
and put it on the second line on the slave controller, which is 9.
-- 
Dick Dunn     rcd@ico.isc.com    uucp: {ncar,nbires}!ico!rcd     (303)449-2870
   ...Are you making this up as you go along?