FIXCOM34.TXT
March 17, 1993

This document covers the following: 

- What is FIXCOM34?
- How will I know that I need FIXCOM34?
- How do I install FIXCOM34?

What is FIXCOM34?  
-----------------
It is an attempt to fix a problem that is inherent on a lot of PC compatibles.
The problem is that as support for communications ports extended beyond COM1
and COM2, the expansion was not supported completely.  Due to a non-uniform
expansion to COM3 and COM4, not all BIOS addresses that are required to support
COM3 and COM4 are correctly initialized.

Under Windows, there is no direct way to set the BIOS addresses and consequently
communications programs under Windows are not successful in accessing COM3 or
COM4.  FIXCOM34 attempts to correct that problem by initializing the BIOS
addresses for COM3 and COM4 to the most widely used default.  Once set, it is
more likely that access to COM3 and COM4 will be successful.

How will I know that I need FIXCOM34?
-------------------------------------
If your communications program complains that the port is 'assigned to a DOS
application' and asks if you want to reassign it, this is one indication that
there may be a problem.  Another indication is that you just don't get any
response from the modem at all when attempting to communicate with it.  It is
easy to check and see what addresses are being used for COM3 and COM4.  You
may not see the correct entries in the Windows Control Panel dialogs, so using
the DOS DEBUG program is your best bet.

After running the command DEBUG from your DOS prompt (you may need to change
the directory to DOS), you'll get a '-' prompt.  At the prompt. type 'd40:0'
and you'll see something like this:

0040:0000 F8 03 F3 02 E8 03 E8 02-BC 03 78 03 00 00 00 00

The 'F8 03' is the address for COM1, and 'F8 02' is the address for COM2.
The 'E8 03' is the address for COM3. and 'E8 02' is the address for COM4.
These addresses are the standard defaults that are normally used.  If your
entries do not match these (if there is no port installed in the machine, the 
address will be '00 00'), and you are having problems using your COMx port,
you probably should try installing FIXCOM34.

How do I install FIXCOM34?
--------------------------
There is one more file that accompanies this text file.  To see if this fix 
works, copy the file FIXCOM34.COM to the root of your hard disk and run it.
Load Windows and see if access to the communications port is successful.  

If it is, to make the change 'permanent', add the command 'FIXCOM34' to your
AUTOEXEC.BAT file and it will be run every time the machine is rebooted.  


If you have any questions about this, please do not hesitate to call the
Software Ventures Technical Support line or send a message to any of the
online services listed in the manuals.