Advantech PCE-3029, User Manual

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77 PCE-3029/4129 User Manual
Appendix A
P
rogramming
the
W
atchdog
Timer
Table A.1: Watchdog Timer Registers
Address of
register (2E) Attribute
Read/Write
Value (2F)& description
87 (hex) -----
Write this address to I/O address port 2E (hex) twice to
unlock the NCT6776D
07 (hex) write Write 08 (hex) to select register of watchdog timer.
30 (hex) write
Write 01 (hex) to enable the function of the watchdog
timer. Disabled is set as default.
F5 (hex) write
Set seconds or minutes as units for the timer. Write 0 to
bit 3: set second as counting unit. [default]. Write 1 to bit
3: set minutes as counting unit
Write 1 to bit 4: Watchdog timer count mode is 1000
times faster.
If bit 3 is 0, the count mode is 1/1000 seconds mode. If
bit 3 is 1, the count mode is 1/1000 minutes mode.
Unlock NCT6776D
Select register of
watchdog timer
Enable the function of
the watchdog timer
Use the function of
Lock NCT6776D
the watchdog timer