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Timer in C
- Thread starter ratzp
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- #3
Are you planning to be doing anything else whilst waiting for the time to elapse?
Since you're using TurboC, which can only create DOS programs, and DOS is the worst operating system for writing anything with any asynchronous behavior, you're in for a hard time.
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Since you're using TurboC, which can only create DOS programs, and DOS is the worst operating system for writing anything with any asynchronous behavior, you're in for a hard time.
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You will need to write your program as TSR that will be triggered by the clock tick. Are you familiar with TSR programming?
Walid Magd (MCP)
The primary challenge of every software development team is to engineer the illusion of simplicity in the face of essential complexity.
-Grady Booch
Walid Magd (MCP)
The primary challenge of every software development team is to engineer the illusion of simplicity in the face of essential complexity.
-Grady Booch
lionelhill
Technical User
... or instead of a full-blown TSR, if the user-defined call is only to be made while your application is running, write an interrupt handler for the 18-times a second user interrupt in DOS, and make your handler keep an eye open for the time and call the correct function.
But do remember that when the call is made, the processor may not have been handling your application, so the data segment may be wrong, the stack may be wrong (or even very, very small) etc.
But do remember that when the call is made, the processor may not have been handling your application, so the data segment may be wrong, the stack may be wrong (or even very, very small) etc.
lionelhill
Technical User
Good point. Back in the old days it was important to daisy-chain any interrupt you diverted, because if you wanted to use it, who knows who else might also have wanted to use it...
But nowadays I can't imagine many people running a DOS environment with several applications. The nice thing about windows dos-boxes is that they lead an independant confined existance, and what goes on in them shouldn't mess up anything else after they're closed.
But nowadays I can't imagine many people running a DOS environment with several applications. The nice thing about windows dos-boxes is that they lead an independant confined existance, and what goes on in them shouldn't mess up anything else after they're closed.
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