DOCUMENT:Q97474  24-JUN-1993  [W_NT]
TITLE   :INF: Serial Port Interrupt Sharing
PRODUCT :Windows NT
PROD/VER:3.10
OPER/SYS:WINDOWS
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows NT Operating System, version 3.1
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Summary:

On all non-MCA (micro channel architecture) bus machines, Microsoft
Windows NT cannot share a single interrupt between any two serial
ports. You can have two serial ports configured to use the same
interrupt, but only one is allowed to be open at a time. The serial
port does not allow sharing the interrupt with anything other than
another serial port.

Additional reference words: 3.10

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