====================================================================== Microsoft(R) Product Support Services Application Note (Text File) WG1001: UPDATED SERIAL.386 DRIVER FOR WINDOWS(TM) FOR WORKGROUPS ====================================================================== Revision Date: 3/94 1 Disk Included The following information applies to Microsoft Windows for Workgroups, version 3.11. ----------------------------------------------------------------------- | INFORMATION PROVIDED IN THIS DOCUMENT AND ANY SOFTWARE THAT MAY | | ACCOMPANY THIS DOCUMENT (collectively referred to as an Application | | Note) IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER | | EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED | | WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR | | PURPOSE. The user assumes the entire risk as to the accuracy and | | the use of this Application Note. This Application Note may be | | copied and distributed subject to the following conditions: 1) All | | text must be copied without modification and all pages must be | | included; 2) If software is included, all files on the disk(s) | | must be copied without modification (the MS-DOS(R) utility | | diskcopy is appropriate for this purpose); 3) All components of | | this Application Note must be distributed together; and 4) This | | Application Note may not be distributed for profit. | | | | Copyright (C) 1994 Microsoft Corporation. All Rights Reserved. | | Microsoft and MS-DOS are registered trademarks and Windows is a | | trademark of Microsoft Corporation. | | Pentium is a trademark of Intel Corporation | |---------------------------------------------------------------------| Introduction ------------ When you use Windows for Workgroups version 3.11 with serial communications software, you may experience the following problems: - If you are using a Pentium(TM)-based machine with a 16550 UART chip, your system stops responding (hangs) if there is data in the chip when the serial communications application attempts to open the communications port. A problem with the 16550 UART implementation causes the chip to become trapped in a mode in which data is always detected in its FIFO buffer. - When you are using communications software, you may be able to make one connection after starting Windows for Workgroups, but any subsequent connections fail and may hang your system. This problem occurs when SERIAL.386 sends an extra NUL character through the port when the communications software calls the CloseComm application program interface (API) function. While this does not normally cause problems, your second connection may fail with some modems. The WG1001 disk included with this Application Note contains an updated SERIAL.386 driver that corrects both of these problems. To install the updated SERIAL.386 file -------------------------------------- 1. Quit Windows for Workgroups. 2. Make a backup copy of the currently installed SERIAL.386 file by typing the following at the MS-DOS command prompt and then pressing ENTER ren :\serial.386 serial.old where : is the location of your Windows SYSTEM subdirectory. For example, if your Windows directory is called WINDOWS and is on drive C, type the following at the MS-DOS command prompt and then press ENTER: ren c:\windows\system\serial.386 serial.old 3. Insert the enclosed WG1001 disk in the appropriate floppy disk drive. 4. To copy the file to the Windows SYSTEM subdirectory, type the following at the MS-DOS command prompt and then press ENTER copy :\serial.386 where is the floppy disk drive containing the WG1001 disk and is the drive and directory of your Windows SYSTEM subdirectory. For example, if the WG1001 disk is in drive A and your Windows directory is called WINDOWS and is on drive C, type the following at the MS-DOS command prompt and then press ENTER: copy a:\serial.386 c:\windows\system