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3-Com / US Robotics modem resource allocation

3-Com / US Robotics modem resource allocation

3-Com / US Robotics modem resource allocation

I've been trying to set up a 3-Com / US Robotics OEM PCI voice fax modem (Model 3CP-2976-OEM) for a user under Windows 98 second edition and am getting some very weird things happening with this hardware based modem.

Basically, the modem only works a minority of the time. When it DOESN'T work, dial up networking is unable to communicate with the modem resulting in an error. When using the MODEM applet in Windows control panel, and going to the DIAGNOSTIC tab and selecting the COM port then clicking MORE INFO, the error message that results is PORT ALREADY OPEN, when there are NO other applications using the modem.

I've had this error before, and it seems that some US Robotics modems (both ISA and PCI) don't like particular IRQ channels or under certain conditions depending on the system environment, certain ICQ channels don't work with the modem. Also, I'm not sure why the Window plug and play assigned COM 5 to this modem when there's only COM 1 and 2 ports in use on the motherboard. I would think that it would select COM 3 and that has been the case with other US Robotics PCI modems I've set up on other computers.

What's even weirder is that I found that the modem sometimes works when the modem is deleted from the Windows device manager, and then rebooting the system so that Windows plug and play sees the device and automatically reinstalls it again. However, this would only work for the FIRST time the modem device is automatically reinstalled by Windows plug and play. If the system is rebooted, the same modem problem would occur again. This has been extremely frustrating and I'm looking for any advise to what might be the cause of this.

Currently, this PCI modem is automatically assigned to IRQ 5, which is fine by me as that is the IRQ that I would prefer to use it on. However, it would be nice to have the modem on COM-3 instead of COM-5. Does anyone know why it is assigned COM-5 instead of COM-3? I recall other situations where recent US Robotics PCI modems would auto assign to COM-3 on ASUS motherboards that had both on-board COM-1 and COM-2 enabled.

I'm not able to manually force assign the COM port to another value, nor the I/O port addresses. When USE AUTOMATIC SETTINGS option is unchecked in the modem device properties resource tab, the resources are still locked in their present values and are unalterable.

I really need to get this working ASAP, so thanks for any help.

RE: 3-Com / US Robotics modem resource allocation

I have a new ASUS board with a similar 2976 modem problem. However, I am also able to dual boot Windows XP which works fine with no effort on installation or use. I still would like to get Windows 98 SE working with my 2976 OEM Modem. Windows 98 SE does have some bug holes, but overall is good. If you would like to corresponed and the post the results, if any, then email to me: spec11@trip.net   
Bill S. 2/5/2004

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