DLL Installs an ISR That Can Signal an Application (68560)
The information in this article applies to:
- Microsoft Windows Software Development Kit (SDK) 3.0
- Microsoft Windows Software Development Kit (SDK) 3.1
This article was previously published under Q68560 SUMMARY
In the Microsoft Windows environment, an interrupt service routine
(ISR) can communicate with an application. n ISR must be in a fixed
code segment in a dynamic-link library (DLL) to ensure that the code
is always in memory and available to service the interrupt. In Windows
3.1, an ISR that supports hardware should be in an installable device
driver to enable Windows to disable the hardware when it switches
between MS-DOS tasks.
HANDLER is a set of sample programs that demonstrate how to install an
ISR, and have the ISR communicate with an application. The HANDLER DLL
installs an ISR, which in turn uses the PostMessage function to notify
the DEMO application (included with HANDLER) that an event has
occurred. The ISR is chained to the keyboard interrupt vector, and the
DEMO application maintains and displays a count of keyboard
interrupts.
This sample program illustrates how an application can detect a
hardware interrupt. This may be useful to a programmer trying to
support a hardware device in the Windows environment.
HANDLER is one of the advanced samples provided with version 3.1 of the
Microsoft Windows SDK. HANDLER can also be found in the Download Center.
Modification Type: | Minor | Last Reviewed: | 8/4/2004 |
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Keywords: | kb16bitonly kbfile kbsample KB68560 |
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