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How to change interrupt numbers for COM ports on PC.

Running Windows95 on a 486.

I have an internal modem that I would like to have on COM3 or COM2. The mouse is a serial mouse on COM1. When I check the interrupts for these ports it is set to 4 for COM1 and COM3 and 3 for COM2.

When I use COM3 for the modem the program that uses the modem thinks that another program is already using the modem and tells me to close the program to use it. My conclusion is that modem and the mouse distubs each other since they have the same interrupt numbers.

When I use COM2 for the modem the entire computer hangs which is strange. Someone told me that perhaps both COM1 and COM2 is dedicated to the mouse.

I hope that the solution to the problem is to change the interrupt number for COM3. Is that correct? If so, how is it done?

Thanks in advance,
Fredrik Rubensson
1 Solution
In order to put the modem on COM2 you'll have to disable that port in BIOS (if it's a newer 486 with onboard I/O) or via jumpers on the adapter card (if it isn't).  Most half way decent modems can be jumpered for COM3 IRQ5 (verify that your sound card isn't there first).  If you don't have the documentation to do so, let somebody know what make and model modem and the info can probably be tracked down.
Since you have a 486 i will assume that you have an I/O board.
Find the jumpers on the I/O board that control the com ports...disable com 2 on the I/O board.

Now Set your modem to the com 2 settings reinstall it in win95

I can expand on this if you need it.

John C. Cook
froderikAuthor Commented:
I have to check the computer before I give further details. (It is not my own but a friend that is currently on vacation.) I will get back to you with details in a month or two...
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