Atmel SAM4L Xplained Pro Evaluation Kit Atmel ATSAM4L-XPRO ATSAM4L-XPRO Data Sheet

42023E–SAM–07/2013

Figure 31-3. SleepWalking™ on Peripheral Events

The PEVC has two clocks connected: one Peripheral Bus clock (CLK_PEVC) and the system
RC oscillator clock (CLK_RCSYS). These clocks are generated by the Power Manager.

CLK_PEVC is required for event propagation and Peripheral Bus operations.

CLK_RCSYS is used for glitch filtering in Event Shapers. It is required for event propagation in
case glitch filtering is turned on for a given generator.

5

incoming Event j propagates to Channel i:

• CLK_USER i request to PM

• TRIG i forwarded to User i

6

CLK_USER i wakes up

7

User i handles the incoming Peripheral Event and signals it to PEVC

8

depending on the Peripheral’s operation, a CPU wake request occurs in case of 
Interrupt processing

9

alternatively, the Peripheral may simply go back to sleep, in which case PM will 
silently shut off CLK_USER i and CLK_PEVC

SleepWalking™ on Peripheral Events

Channel

i

PEVC

EVS

j

Generator

j

User

i

TRIG i

EVT j

RDY i

CLK_USER i

Power Manager

CLK_USER i

Wake CPU

IRQ USER i

1

2

5

7

8

6

5

4

Wake Clock Sources

CLK_PEVC

3