ATSAM3S ATMEL [ATMEL Corporation], ATSAM3S Datasheet - Page 40

• Manufacturer Part Number: ATSAM3S
• Description: AT91 ARM Cortex M3-based Processor
• Manufacturer: ATMEL [ATMEL Corporation]

Figure 10-3. SAM3S Power Management Controller Block Diagram
10.7
10.8
10.9
40
Watchdog Timer
SysTick Timer
Real Time Timer
SAM3S Summary
MAINCK
PLLBCK
PLLACK
The SysTick calibration value is fixed at 8000 which allows the generation of a time base of 1 ms
with SystTick clock at 8 MHz (max HCLK/8 = 64 MHz/8).
• 16-bit key-protected only-once-Programmable Counter
• Windowed, prevents the processor to be in a dead-lock on the watchdog access.
• 24-bit down counter
• Self-reload capability
• Flexible System timer
• Real Time Timer, allowing backup of time with different accuracies
SLCK
– 32-bit free-running back-up counter
– Integrates a 16-bit programmable prescaler running on slow clock
Master Clock Controller
MAINCK
PLLACK
PLLBCK
PLLBCK
SLCK
/1,/2,/4,...,/64
Prescaler
Programmable Clock Controller
USB Clock Controller
/1,/2,/4,...,/64
Prescaler
Sleep Mode
ON/OFF
Clock Controller
Processor
Controller
ON/OFF
Divider
Clock
Peripherals
ON/OFF
/8
HCK
int
SystTick
FCLK
MCK
periph_clk[..]
pck[..]
UDPCK
6500AS–ATARM–11-Dec-09