386 interrupts, pcnfs

[Steven H. Izen]

In your article <22902 at louie.udel.EDU> you ask:

>In particular, the standard PC boards only seem to support the 'non cascaded'
>interrupts on the AT.  How can you run 2 standard serial ports, a parralel
>port, buss mouse, ethernet board, etc??  On the unix server side the drivers
>might be smart enough to poll multiple devices on 1 interrupt line.
>What can be about the pcnfs dos pc clients??


I had similar problems getting 2 serial ports, 2 parallel ports, a tape drive,
and a bus mouse all to work under 386/ix 2.0.1.  I ran out of interrupts as
well.  My solution was a hardware hack:  I redirected the interrupts from both
parallel ports to the cascaded interrupt controller, more specifically 11 and
12.  ISC's parallel driver works with these interrupts.  Their serial driver
can't handle this hack-I learned that the hard way.  Fortunately I did the 
hardware modification in such a way that restoring my serial board to interrupt
4 was easy. (I just flipped a dip switch).  
	Incidentally, the only side effect of the interrupt hack that I've
discovered so far is that under real-mode DOS (yuck, but I have to run
Mathematica under DOS) the Logitech mouse driver can't find any interrupt
jumper even though I have it on int 5.  (It does work under VPIX, however).
Hey ISC, this may be a first!  Something works under VPIX but not real-mode
DOS! :-)  Anyway, since DOS printing is not interrupt driven, the hack doesn't
affect printing under real-mode DOS.


Steve Izen

-- 
Steve Izen: {sun,decvax,uunet}!cwjcc!skybridge!izen386!steve
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