MS-DOS/Win16 Serial Communication Applications on NT

 Last reviewed: May 6, 1997
Article ID: Q93218

The information in this article applies to:
  • Microsoft Windows NT operating system version 3.1

When running MS-DOS or Windows version 3.1 serial communications applications that directly access serial port hardware, you may enhance performance of these applications by using software handshaking (xon/xoff) instead of hardware handshaking (cts/rts).

Because hardware must be virtualized under NT, checking the cts/rts signals directly will incur an unavoidable performance degradation. Using xon/xoff handshaking avoids this problem since xon/xoff handshaking does not require accessing the serial port hardware directly.

Note that this does not apply to Windows version 3.x or Win32 applications that correctly use the Comm APIs to do communications.

Additional query words: prodnt handshaking cts rts
Keywords : kbhw nthw
Version : 3.1
Platform : WINDOWS

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Last reviewed: May 6, 1997
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