PC Access for Windows Reference Guide

for PC Access Version 4.30

FIFO buffer for COMn is not or may not be enabled

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 your 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.

Last modification date: Friday, January 17, 2003 00:58:48