PC Access for Windows Reference Guide

for PC Access for Windows 4.30.158

FIFO buffer for COMn is not or may not be enabled

This message should only appear if all these conditions are true:

· You finished setting up your modem in PC Access, either on the Setup Assistant - Modem Setup window or the Modem Setup window.

· You are running Windows 3.1, Windows 3.11, or Windows 3.11 for Workgroups. PC Access checks the version of Windows you are running before displaying this message.

· PC Access believes your COM port is not buffering incoming data as efficiently as it could.

When this message appears, PC Access has just examined the SYSTEM.INI file in your Windows directory to see if it has a COMnFIFO entry in the [386Enh] section, and if so, what value the entry has. (The n in COMnFIFO is the number of the COM port you have currently selected on the Modem Setup window.)

If PC Access message says "FIFO buffer may not be enabled," your SYSTEM.INI file does not have a COMnFIFO entry. This means your COM port's 16550 UART may be emulating a non-buffering 8250 UART under Windows. If it is, you are more likely to have communication errors.

If your SYSTEM.INI has a COMnFIFO entry, and this entry has a value other than 1 (one), the 16550 UART is definitely emulating a non-buffering 8250 UART under Windows. This means you are more likely to have communication errors.

PC Access can correct this by changing the COMnFIFO entry in your SYSTEM.INI file. For example, if you selected COM2 on the Modem Setup window, and you select Yes on the dialog displaying this message, PC Access will add this line to your SYSTEM.INI file:

COM2FIFO=1

You will need to exit PC Access and restart Windows for this change to take effect.

If you see this message when you click the Done button on the Setup Assistant - Modem Setup window, PC Access will attempt to change the COMnFIFO entry in your SYSTEM.INI file unconditionally.

If you get this message under Windows 95, Windows 98, Windows 2000, or Windows NT 4.0, PC Access is probably detecting your version of Windows incorrectly. If the error persists, you can try enabling the FIFO buffer on your COM port by following these directions:

http://www.mfm.com/support/std_procedures/commerr.html#win95uart

If that does not correct the problem, follow the instructions for an Internal Error.

This topic has changed for PC Access 4.30 (Monday, July 24, 2000).

Last modification date: Friday, January 17, 2003 00:58:53