DOCUMENT:Q103411  25-AUG-1993  [W_NT]
TITLE   :Windows NT Parallel Ports Do Not Use Interrupts
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
 - Microsoft Windows NT Advanced Server, version 3.1
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In Windows NT, parallel ports do not use any hardware interrupt
request lines (IRQs).
 
The Windows NT parallel port driver is thread-based, and the port is
polled at background priority. This eliminates a number of potential
hardware conflicts with other devices that might want to use IRQ 7 or
5, which used to be the parallel port interrupts.
 
NOTE: If you boot OS/2 or MS-DOS, you still need to check for IRQ
conflicts; the Windows NT port driver will not be used.
 
Additional reference words: 3.10
KBCategory:
KBSubCategory: PRT

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