Техническая Спецификация для Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK
Модели
AT91SAM9M10-G45-EK
111
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
16. Watchdog Timer (WDT)
16.1
Description
The Watchdog Timer can be used to prevent system lock-up if the software becomes trapped in a deadlock. It fea-
tures a 12-bit down counter that allows a watchdog period of up to 16 seconds (slow clock at 32.768 kHz). It can
generate a general reset or a processor reset only. In addition, it can be stopped while the processor is in debug
mode or idle mode.
tures a 12-bit down counter that allows a watchdog period of up to 16 seconds (slow clock at 32.768 kHz). It can
generate a general reset or a processor reset only. In addition, it can be stopped while the processor is in debug
mode or idle mode.
16.2
Embedded Characteristics
• 16-bit key-protected only-once-Programmable Counter
• Windowed, prevents the processor to be in a dead-lock on the watchdog access
16.3
Block Diagram
Figure 16-1.
Watchdog Timer Block Diagram
= 0
1
0
set
reset
read WDT_SR
or
reset
or
reset
wdt_fault
(to Reset Controller)
set
reset
WDFIEN
wdt_int
WDT_MR
SLCK
1/128
12-bit Down
Counter
Current
Value
WDD
WDT_MR
<= WDD
WDV
WDRSTT
WDT_MR
WDT_CR
reload
WDUNF
WDERR
reload
write WDT_MR
WDT_MR
WDRSTEN