COMxFIFO Does Not Properly Understand True and False

ID: Q84873


The information in this article applies to:
  • Microsoft Windows versions 3.1, 3.11


SYMPTOMS

The SYSTEM.INI [386Enh] setting COMxFIFO= does not correctly understand True/False, On/Off, or Yes/No. Using any non-numerical value sets the switch to "0" and therefore disables the FIFO.


CAUSE

The COMxFIFO= setting is not fully Boolean aware.


STATUS

Microsoft has confirmed this to be a problem in Windows version 3.1. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.


WORKAROUND

Use the following settings: COMxFIFO=1 (On)

-or-
COMxFIFO=0 (Off)


MORE INFORMATION

This switch is used to enable or disable Windows 3.1 support for Windows-based applications using a COM port with a 16550 Universal Asynchronous Receiver Transmitter (UART). The 16550 has a 16-byte character FIFO buffer, or first-in, first-out buffer.

The SYSINI.WRI file from the Microsoft Windows Resource Kit (WRK) for version 3.1 incorrectly identifies TRUE/FALSE as functioning with this switch. Page 196 of the WRK guide incorrectly identifies On/Off as functioning with this switch.

For more information on this setting, query on:

COMMQ&A and windows 3.1

Additional query words: 3.10 3.11 crc xmodem documentation error doc err

Keywords :
Version : WINDOWS:3.1,3.11
Platform : WINDOWS
Issue type :


Last Reviewed: October 1, 1999
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