ICP DAS USA's WDT-01 Intelligent Watchdog Timer Card with Toolkit for Windows DOS/95/98/NT/2000/XP and Drivers for Linux: Amazon.com: Industrial & Scientific
The Cortex-M3 Embedded Systems: LM3S9B96 Microcontroller – Watchdog Timers Refer to Chapter 11 in the reference book “Stellaris® LM3S9B96 Microcontroller. - ppt download