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dib

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Three COM ports <-> Win95

hi,
I need three serial ports in my PC (Win95). I bought a serial card where I can configure the interupt
between 2-15 and the I/O base between 200h-400h.
I read in the description of the card, that I can configure the COM port IRQ to 3 or 4
(same as COM1/COM2). But in that case I'm not able to use the COM ports on the same IRQ, at the same time!  
Question 1: Is that correct?
So I configured the thrird COM port to IRQ 5. In the device manager (in Win95 control settings) I can see
the third COM port. The problem: In the device manager the port can only be set to IRQ 3 or 4!!
Question 2: How to configure the third port to IRQ 5 (registry?!)?
regards dib
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dib

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Edited text of question
"But in that case I'm not able to use the COM ports on the same IRQ, at the same time!  
Question 1: Is that correct?"
Yes, that is correct.


"The problem: In the device manager the port can only be set to IRQ 3 or 4!! Question 2: How to configure the third port to IRQ 5 (registry?!)? "
Have you tried to "uncheck" the USE AUTOMATIC SETTINGS?  Are there jumpers on the card that are set correctly?  Does DEVICE MANAGER show ANY available IRQs?

If you already have two COM ports installed on the motherboard, with COM1 & COM2 set at standard defaults, then set your new card's port to COM3, using IRQ5 if you wish.
Please explain what you are trying to do so we might better assist you.
Regards,
Ralph

I can confirm what ryans says about COM ports with a shared interrupt being mutually exclusive.  I used to have an external modem which would disable my mouse :)
ASKER CERTIFIED SOLUTION
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wjmarks

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hmmm. "force mode"  that's a good one.  
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ASKER

The jumpers on the card are set correctly.
I tried to "uncheck" the USE AUTOMATIC SETTINGS to set port 3 to IRQ 5 but
the choices are only IRQ 3 and 4.
The backgroud: I wrote a program which writes data to one port and read data from
the other. I need a third one for the mouse ... #@*!
I think I have to buy a PS2 card :-(
So tell us what this "force mode" that you found and how did it fix your problem!
Look in com port or modem section of device manager.  From what I am told it is a software thing.  It is not under all systems.  The computer I was working on was out of state and the person who owns it has no idea as to how to help me find it...sorry!


By the sounds of your last comment, the problem is not solved yet.  Is it?