🚀 go-pugleaf

In <93021.35673.LJ01066@LMSC5.IS.LMSC.LOCKHEED.COM> LJ01066@LMSC5.IS.LMSC.LOCKHEED.COM writes:

>I need information on how to use comm ports 3&4 if I already have devices
>on 1&2.  What I really want to know is if I can put two modem cards in
>my system one on port 1 the other on port 2 and assign my mouse to be on
>comm 3 or 4.  

Your mouse is probably going to insist on being on COM1 or COM2.  Move
the modem cards.  Also, check the documentation on the cards to see if
they can use 'non-standard' interrupts.  Ideally, what you want to do
is put the mouse on COM1 and the other two devices on COM2 and COM3.  

>I already have an expensive fax/modem card but modem speed
>is limited to 2400 and I would like to install a 9600 modem only card
>without loosing my other card, i.e. switch between the two or at least
>when using the 9600 modem being able to use my mouse too.  E-mail or posted
>replies greatly appreciated.  Thanks to all who help in advance.

The problem is that COM3 and COM4 don't have their own standard IRQ
numbers.  When two devices share the same IRQ number, they will
conflict if you try to use them both at the same time.  Check your FAX
and modem card and see if they will let you set for COM3 or COM4 using
an IRQ other than 3 or 4.  Most devices will allow you to set them to
IRQ2-5.  Set the device you put at COM3 to IRQ2, and tell your
software to expect it on IRQ9 (assuming an AT or better machine --
IRQ2 is the Cascade interrupt).  This will let you use all three
devices at once.

If none of them will use a non-standard IRQ, put the mouse on the COM
port (1 or 2) that is using the 'non-common' IRQ (the one that isn't
being used by another device).  Then put the FAX and modem on the
other two.  The 'standard' IRQ's are usually:

PORT		ISA/EISA	MCA
===========	============	===========
COM1		IRQ4		IRQ4*
COM2		IRQ3*		IRQ3
COM3		IRQ4		IRQ3
COM4		IRQ3		IRQ3

Put your mouse on the one with the '*' beside it, depending on what
kind of bus your machine has, and put the other two devices on the
other two of COM1-3.

Anyway, hope this helps.

-- 
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
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Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.