Information

Section Number Title Page
22.4.3 EWM Counter..............................................................................................................................................498
22.4.4 EWM Compare Registers............................................................................................................................498
22.4.5 EWM Refresh Mechanism...........................................................................................................................499
Chapter 23
Watchdog Timer (WDOG)
23.1 Introduction...................................................................................................................................................................501
23.2 Features.........................................................................................................................................................................501
23.3 Functional Overview.....................................................................................................................................................503
23.3.1 Unlocking and Updating the Watchdog.......................................................................................................504
23.3.2 The Watchdog Configuration Time (WCT).................................................................................................505
23.3.3 Refreshing the Watchdog.............................................................................................................................506
23.3.4 Windowed Mode of Operation....................................................................................................................506
23.3.5 Watchdog Disabled Mode of Operation......................................................................................................506
23.3.6 Low Power Modes of Operation..................................................................................................................507
23.3.7 Debug Modes of Operation..........................................................................................................................507
23.4 Testing the Watchdog...................................................................................................................................................508
23.4.1 Quick Test....................................................................................................................................................508
23.4.2 Byte Test......................................................................................................................................................508
23.5 Backup Reset Generator...............................................................................................................................................510
23.6 Generated Resets and Interrupts...................................................................................................................................510
23.7 Memory Map and Register Definition..........................................................................................................................511
23.7.1 Watchdog Status and Control Register High (WDOG_STCTRLH)...........................................................512
23.7.2 Watchdog Status and Control Register Low (WDOG_STCTRLL)............................................................514
23.7.3 Watchdog Time-out Value Register High (WDOG_TOVALH).................................................................514
23.7.4 Watchdog Time-out Value Register Low (WDOG_TOVALL)..................................................................515
23.7.5 Watchdog Window Register High (WDOG_WINH)..................................................................................515
23.7.6 Watchdog Window Register Low (WDOG_WINL)...................................................................................516
23.7.7 Watchdog Refresh Register (WDOG_REFRESH)......................................................................................516
23.7.8 Watchdog Unlock Register (WDOG_UNLOCK).......................................................................................516
K20 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc. 19