Octagon 5266, Справочное руководство

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Watchdog function definitions using enhanced INT 17h handler
This section provides definitions for the watchdog functions using the built-in
INT17 handler. The INT17 handler is designed for DOS based applications. If you
use a different operating system and the watchdog functions are required for your
application, you must supply drivers to access the watchdog. Contact Octagon
Systems for more information on the drivers.
Enable watchdog
Function: fdh
Subfunction: 01h
Purpose: To enable the watchdog.
Calling registers: AH fdh
AL 01h
BX timeout period; the value entered here is
the number of seconds, up to ffffh
DX ffffh
Return registers: None
Comments: This function enables the watchdog. Once
the watchdog is enabled, it has to be strobed at
a period greater than the timeout period
specified or until the watchdog is disabled.
Otherwise, a system reset will occur.
Programming example:
/* Inline assembly code for Borland C++ 3.1 */
/* set watchdog to 10 second timeout */
asm {
mov ax,0fd01h
mov bx,1
mov dx,0ffffh
int 17h
}
Strobe watchdog
Function: fdh
Subfunction: 02h
Purpose: To strobe the watchdog.
Calling registers: AH fdh
AL 02h
BX timeout period; the value entered here is
the number of seconds, up to ffffh
DX ffffh
Return registers: None
Comments: This function strobes the watchdog. Once the
watchdog is enabled, it has to be strobed at a
period greater than the timeout period or until
the watchdog is disabled. Otherwise, a system
reset will occur.
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