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NOTE:
The following discussion applies to DOS environment. It is recommended you contact CYBERRESEARCH support or visit our website for specific drivers for more sophisticated operating systems, e.g., Windows and Linux.
The Watchdog Timer is provided to ensure that standalone systems can always recover from catastrophic conditions that cause the CPU to crash. This condition may have occurred by external EMI or a software bug. When the CPU stops working correctly, Watchdog Timer will either perform a hardware reset (cold boot) or a
A BIOS function call (INT 15H) is used to control the Watchdog Timer:
INT 15H:AH – 6FHAL – 2: Set the Watchdog Timer’s period
BL :
You have to call
A tolerance of at least 10% must be maintained to avoid unknown routines within the operating system (DOS), such as disk I/O that can be very
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