ATSAM3S-EK Atmel, ATSAM3S-EK Datasheet - Page 433

• Manufacturer Part Number: ATSAM3S-EK
• Description: KIT EVAL FOR ATSAM3S4C
• Manufacturer: Atmel
• Series: SAM3Sr
• Type: MCUr

Specifications of ATSAM3S-EK

• Contents: Board, Cables, Power Supply
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex-M3
• Kit Contents: Board
• Features: TFT Colour LCD Display, SD/MMC Interface
• Svhc: No SVHC (15-Dec-2010)
• Rohs Compliant: Yes
• For Use With/related Products: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

26.11 Fast Startup
6500C–ATARM–8-Feb-11
The device allows the processor to restart in less than 10 microseconds while the device is in
Wait mode. The system enters Wait mode either by writing the WAITMODE bit at 1 in the PMC
Clock Generator Main Oscillator Register (CKGR_MOR), or by executing the WaitForEvent
(WFE) instruction of the processor while the LPM bit is at 1 in the PMC Fast Startup Mode Reg-
ister (PMC_FSMR). Waiting for MOSCRCEN bit to be cleared is strongly recommended to
ensure that the core will not execute undesired instructions.
Important: Prior to asserting any WFE instruction to the processor, the internal sources of
wakeup provided by RTT, RTC and USB must be cleared and verified too that none of the
enabled external wakeup inputs (WKUP) hold an active polarity.
A Fast Startup is enabled upon the detection of a programmed level on one of the 16 wake-up
inputs (WKUP) or upon an active alarm form the RTC, RTT and USB Device Controller. The
polarity of the 16 wake-up inputs is programmable by writing the PMC Fast Startup Polarity Reg-
ister (SUPC_FSPR).
The Fast Restart circuitry, as shown in
startup signal to the Power Management Controller. As soon as the fast startup signal is
asserted, this automatically restarts the embedded 4/8/12 MHz Fast RC oscillator.
Figure 26-4. Fast Startup Circuitry
Each wake-up input pin and alarm can be enabled to generate a Fast Startup event by writing at
1 the corresponding bit in the Fast Startup Mode Register SUPC_FSMR.
WKUP15
WKUP0
WKUP1
RTT Alarm
RTC Alarm
USB Alarm
FSTP0
FSTP1
FSTP15
FSTT0
FSTT1
FSTT15
RTTAL
RTCAL
USBAL
Figure
26-4, is fully asynchronous and provides a fast
SAM3S Preliminary
fast_restart
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