Watchdog Timer; Introduction; Functions - Texas Instruments Tiva TM4C123GH6PM User Manual

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Watchdog Timer

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341

Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341

25.1 Introduction
The watchdog timer API provides a set of functions for using the watchdog timer module. Functions
are provided to deal with the watchdog timer interrupts, and to handle status and configuration of
the watchdog timer.
The watchdog timer module's function is to prevent system hangs. The watchdog timer module
consists of a 32-bit down counter, a programmable load register, interrupt generation logic, and a
locking register. Once the watchdog timer has been configured, the lock register can be written to
prevent the timer configuration from being inadvertently altered.
The watchdog timer can be configured to generate an interrupt to the processor upon its first time-
out, and to generate a reset signal upon its second timeout. The watchdog timer module generates
the first timeout signal when the 32-bit counter reaches the zero state after being enabled; en-
abling the counter also enables the watchdog timer interrupt. After the first timeout event, the 32-bit
counter is reloaded with the value of the watchdog timer load register, and the timer resumes count-
ing down from that value. If the timer counts down to its zero state again before the first timeout
interrupt is cleared, and the reset signal has been enabled, the watchdog timer asserts its reset
signal to the system. If the interrupt is cleared before the 32-bit counter reaches its second timeout,
the 32-bit counter is loaded with the value in the load register, and counting resumes from that
value. If the load register is written with a new value while the watchdog timer counter is counting,
then the counter is loaded with the new value and continues counting.
25.2 Functions
Functions
void ROM_WatchdogEnable
void ROM_WatchdogIntClear
void ROM_WatchdogIntEnable
uint32_t
void ROM_WatchdogIntTypeSet
void ROM_WatchdogLock
bool ROM_WatchdogLockState
uint32_t
void ROM_WatchdogReloadSet
void ROM_WatchdogResetDisable
void ROM_WatchdogResetEnable
bool ROM_WatchdogRunning
void ROM_WatchdogStallDisable
void ROM_WatchdogStallEnable
April 8, 2013
(uint32_t ui32Base)
(uint32_t ui32Base)
(uint32_t ui32Base)
ROM_WatchdogIntStatus
(uint32_t ui32Base)
(uint32_t ui32Base)
ROM_WatchdogReloadGet
(uint32_t ui32Base)
(uint32_t ui32Base, bool bMasked)
(uint32_t ui32Base, uint32_t ui32Type)
(uint32_t ui32Base)
(uint32_t ui32Base, uint32_t ui32LoadVal)
(uint32_t ui32Base)
(uint32_t ui32Base)
(uint32_t ui32Base)
(uint32_t ui32Base)
Watchdog Timer
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