RM0082
BS_Watchdog timer
Doc ID 018672 Rev 1
313/844
16 BS_Watchdog
timer
16.1 Overview
Within its basic subsystem, the device provides an ARM watchdog module. It consists of a
32 bit down counter with a programmable time-out interval that has the capability to
generate an interrupt and a reset signal on timing out. The watchdog module is intended to
be used to apply a reset to a system in the event of a software failure.
Main features of the Watchdog module are:
●
32 bit down counter with a programmable time-out interval.
●
Separate watchdog clock with its clock enable for flexible control of the time-out
interval.
●
Interrupt output generation on time-out.
●
Reset signal generation on time-out, if the interrupt from the previous time-out remains
unserviced by software.
●
Lock register to protect registers from being altered by runaway software.
●
Identification registers that uniquely identify the watchdog module. These can be used
by software to automatically configure itself.
●
An APB slave allowing access to all registers.
16.2 Block
diagram
shows a simplified block diagram of the watchdog module.
Figure 27.
Watchdog module block diagram
Free Running
Counter
Load Register Control Register
32-bit down counter
Value Register
Interrupt and
Reset generation
Raw Interrupt Status Register
Masked Interrupt Status Register
Interrupt Clear Register
AMBA APB Interface
ID Registers
Lock Register
Integration Test Register
WDOGINT
WDOGRES
AMBA APB
Signals
WDOGCLK
WDOGCLKEN
WDOGRESn