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

The debouncing period duration is configurable. The period is made for all debouncers (i.e., the duration cannot be 

adjusted separately for each debouncer). The number of successive identical samples to wake up the system can 

be configured from 2 up to 8 in the LPDBC field of SUPC_WUMR. The period of time between two samples can be 

configured by programming the TPERIOD field in the RTC_MR. Power parameters can be adjusted by modifying 

the period of time in the THIGH field in RTC_MR.
The wake-up polarity of the inputs can be independently configured by writing WKUPT0 and/ or WKUPT1 fields in 

SUPC_WUMR.
In order to determine which wake-up/tamper pin triggers the system wake-up, a status flag is associated for each 

low-power debouncer. These flags are read in SUPC_SR.
A debounce event (tamper detection) can perform an immediate clear (0 delay) on the first half the general-

purpose backup registers (GPBR). The LPDBCCLR bit must be set in SUPC_MR. 
Note that it is not mandatory to use the RTCOUTx pin when using the WKUP0/WKUP1 pins as tampering inputs in 

any mode. Using the RTCOUTx pin provides a “sampling mode” to further reduce the power consumption of the 

tamper detection circuitry. If RTCOUTx is not used, the RTC must be configured to create an internal sampling 

point for the debouncer logic. The period of time between two samples can be configured by programming the 

TPERIOD field in RTC_MR.

 illustrates the use of WKUPx without the RTCOUTx pin.

MCU

WKUP0

WKUP1

RTCOUTx

Pull-down

Resistors

GND

GND

GND