ADLINK Technology cPCI-3615 Series User Manual

Contents

ADLINK Technology cPCI-3615 Series User Manual Manual pdf 81 page image

Utilities 67cPCI-36157 Utilities7.1 Watchdog TimerThis section describes the operation of the cPCI-3615’s watchdogtimer (WDT). The primary function of the WDT is to monitor thecPCI-3615's operation and to reset the system if a software appli-cation fails to function as programmed. The following WDT func-tions may be controlled using a software application:X enabling and disablingX reloading timeout valueThe cPCI-3615 custom WDT circuit is implemented using theinternal I/O of the ITE SuperIO IT8783 which is at 2Eh of LPC. Thebasic functions of the WDT include:X Starting the timer countdownX Enabling or disabling WDTX Enabling or disabling WDT countdown LED ONX Reloading the timeout value to keep the watchdog from tim-ing outX Setting the range of the timeout period from 1 second or minuteto maximum 65635 seconds or minutesX Sending a RESET signal to the system when the watchdogtimes outUsing the Watchdog in an ApplicationThe following section describes using the WDT functions in anapplication. The WDT reset function is explained in the previoussection. This can be controlled through the registers in thecPCI-3615's SuperIO.An application using the reset feature enables the watchdog func-tion, sets the count-down period, and reloads the timeout valueperiodically to keep it from resetting the system. If the timer count-down value is not reloaded, the watchdog resets the system hard-ware after its counter reaches zero.For a detailed programming sample, refer to the sample code pro-vided in the ADLINK All-In-One CD. You can find it in the followingdirectory: X:\cPCI\cPCI-3615\WDT.