Re: including ISR in euphoria program
- Posted by Robert Craig <72614.1667 at COMPUSERVE.COM> Oct 07, 1996
- 1777 views
Jacques Deschenes writes: > As I'm writing an include file to play wave file on sound blaster card > I'm stock with a bug regarding the interrupt service routine. it's > doesn't work. > I need to known if ISR are running in protected mode or real, or virtual > mode > Here is my ISR code. As you know, Euphoria uses the Causeway DOS extender. This allows the ex.exe interpreter run in 32-bit protected mode for most computations. However to remain compatible with DOS, the DOS extender must switch into real mode to call operating system functions such as I/O etc. According to the Causeway DOS extender manual ... "Hardware interrupts are always reflected to protected mode handlers even when signalled during real mode operations. This ensures that protected mode applications always retain control without requiring you to patch real mode interrupt vectors." Apparently there is an interrupt vector table for real mode and another one for protected mode. Causeway has a routine that lets you set an interrupt address in the protected mode interrupt table. If you need more help let me know. I have a few code examples and more documentation that might be useful. I don't have much practical experience with handling hardware interrupts on PCs. Maybe some other people out there have done this sort of thing? Regards, Rob Craig Rapid Deployment Software