Changing COM port mapping under Win 95/98

Title: Changing COM port mapping under Win 95 and Win 98
Keywords: Changing COM port mapping under Win 95 and Win 98
Date: August 5, 1998

KDB Number: kdb-218
Revision: 0.01
Author: Support
Distribution: External

By default the Windows 95 driver for the DFlex and Blueheat MPSA's (MultiPort Serial Adapter's) start the serial port definitions at COM5. It has been desirable to change the definition(s) of the first two ports of the MPSA from COM5 and/or COM6 to COM3 and/or COM4. (Depending if you want to change the assignment for two ports or just one port.) In order to do this, you would need to modify registry the entries for COM5 and/or COM6.

After the Connect Tech MPSA has been successfully installed and the driver has added the additional ports into the Device Manager, you will need to take the following steps. For this example we will modify the first Blue Heat port (COM5) to be renamed as COM3.

1. Confirm there does not exist a COM3 in the Start->Settings->Control Panel->System->Device Manager->Ports (COM & LPT) section.
2. Run REGEDIT.
3. Search for COM5 - this will be the first port on the Blueheat. When found, the key would look something like the following:
My Computer\HKEY_LOCAL_MACHINE\Enum\MF\CHILD0000\PCI&VEN_11B0&DEV_0001&BUS_00&DEV_11&FUNC_00

4. You will need to change all references for COM5 to COM3. Generally these will be the following keys:
DeviceDesc, FRIENDLYNAME and PORTNAME.
Perform this modification to all entries in the
My Computer\HKEY_LOCAL_MACHINE\Enum\MF\CHILD0000
directory entries that have references to COM5.

5. After the modifications, exit REGEDIT. this will save the new registry entry.

6. Now upon reboot, you should see the first Blue Heat port defined as COM3, instead of COM5.

7. You can confirm this association by connecting a loopback connector onto the first port of the Blue Heat, and performing a loopback test with Hyperterminal.

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