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Q84873: COMxFIFO Does Not Properly Understand True and False

Article: Q84873
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.1,3.11
Operating System(s): 
Keyword(s): 
Last Modified: 05-OCT-1999

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The information in this article applies to:

- Microsoft Windows versions 3.1, 3.11 
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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          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin310 kbWin311
Version           : WINDOWS:3.1,3.11

=============================================================================

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