ICP WAFER-5823, Руководство пользователя

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Appendix A. Watchdog Timer
The Watchdog Timer is a device 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
normally, hardware on the board will perform hardware reset
(cold boot) to bring the system back to a known state.
Three I/O ports control the Watchdog Timer.
443 Write Set Watchdog Time period
443 (hex) Read
Enable the refresh the Watchdog
Timer
043/843 (hex) Read Disable the Watchdog Timer
Prior to enable the Watchdog Timer, user has to define Timer
first. The output data is a value of time interval and the range
of the value is from 01(hex) to FF (hex) and time interval 1 sec
to 255 sec.
Data Time Interval
01 1 sec
02 2 sec
03 3 sec
04 4 sec
.
.
.
.
.
.
FF 255 sec