Copyright © 2011 NEXCOM International Co., Ltd. All Rights Reserved.
66
DNA 1120/1120A User Manual
Appendix A: Watchdog Timer
a
PPendix
a: W
atChdog
t
imer
Watchdog Timer Setting
DNA 1120/1120A features a watchdog timer that resets the CPU or gener-
ates an interrupt if the processor stops operating for any reason. This feature
ensures system reliability in industrial standalone or unmanned environ-
ments.
CRF6 (Default 0x00)
Watchdog Timer Time-out Value
Writing a non-zero value to this register causes the counter to load the value
to Watchdog Counter and start counting down. If Bit 7 and Bit 6 are set,
any Mouse Interrupt or Keyboard Interrupt event will also cause the reload
of previously-loaded non-zero value to Watchdog Counter and start count-
ing down. Reading this register returns current value in Watchdog Counter
instead of the Watchdog timer time-out value.
Watchdog Timer Time-out Value
BIT
Definition
7-0
0x00 time-out disabled
0x01 time-out occurs after 1sec./min.
0x02 time-out occurs after 2 sec./min.
0x03 time-out occurs after 3 sec./min.
•
•
0xFF time-out occurs after 255 sec./min.
