35
Appendix B - Watchdog Timer
This appendix describes use of the watchdog timer (WDT) function library for the PXI-63980
controller. The watchdog timer is a hardware mechanism resetting the system when the
operating system or application halts. After starting, periodic reset of the watchdog timer
in the application before expiry is required. Once the watchdog timer expires, a hardware-
generated signal is sent to reset the system.
B.1 WDT Function Library
B�1�1 InitWDT
Description
Initializes watchdog timer function. InitWDT must be called before the invocation of any
other WDT function.
Supported Controllers
PXI-63980, PXI-63930,
Syntax
C/C++
◦ BOOL InitWDT()
Visual Basic
◦ InitWDT() As Boolean
Parameter
None
Return Code
True
If watchdog timer is successfully initialized
False
If watchdog timer fails to initialize
B�1�2 SetWDT
Description
Sets the timeout value for watchdog timer. The timeout value uses seconds as a unit.
ResetWDT or StopWDT should be called prior to expiration of the watchdog timer,
or the system will be reset.
Supported Controllers
PXI-63980, PXI-63930,
Syntax
C/C++
◦ BOOL SetWDT(unsigned long second)
Visual Basic
◦ InitWDT(ByVal second as Long) As Boolean
