Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

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SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

3. Set Flash wait state to 0.
4. Set the LPM bit in the PMC Fast Startup Mode Register (PMC_FSMR). 
5. Execute the Wait-For-Event (WFE) instruction of the processor.

In both cases, depending on the value of the field Flash Low Power Mode (FLPM), the Flash enters three different 

modes:



FLPM = 0 in Standby mode (Low consumption)



FLPM = 1 in Deep power-down mode (Extra low consumption)



FLPM = 2 in Idle mode. Memory ready for Read access

 summarizes the power consumption, wake-up time and system state in wait mode.

The purpose of sleep mode is to optimize power consumption of the device versus response time. In this mode, 

only the core clock is stopped. The peripheral clocks can be enabled. The current consumption in this mode is 

application dependent.
This mode is entered via Wait for Interrupt (WFI) or WFE instructions.
The processor can be awakened from an interrupt if the WFI instruction of the Cortex-M4 is used or from an event 

if the WFE instruction is used.

The modes detailed above are the main low-power modes. Each part can be set to on or off separately and wake 

up sources can be individually configured. 

 below shows a summary of the configurations of the low-

power modes.