Datasheet

1197
42023E–SAM–07/2013
ATSAM4L8/L4/L2
20 Watchdog Timer (WDT) ....................................................................... 481
20.1 Features ........................................................................................................481
20.2 Overview ........................................................................................................481
20.3 Block Diagram ...............................................................................................481
20.4 Product Dependencies ..................................................................................481
20.5 Functional Description ...................................................................................482
20.6 User Interface ................................................................................................489
20.7 Module Configuration ....................................................................................500
21 External Interrupt Controller (EIC) ..................................................... 501
21.1 Features ........................................................................................................501
21.2 Overview ........................................................................................................501
21.3 Block Diagram ...............................................................................................501
21.4 I/O Lines Description .....................................................................................502
21.5 Product Dependencies ..................................................................................502
21.6 Functional Description ...................................................................................502
21.7 User Interface ................................................................................................506
21.8 Module Configuration ....................................................................................522
22 Frequency Meter (FREQM) .................................................................. 523
22.1 Features ........................................................................................................523
22.2 Overview ........................................................................................................523
22.3 Block Diagram ...............................................................................................523
22.4 Product Dependencies ..................................................................................523
22.5 Functional Description ...................................................................................524
22.6 User Interface ................................................................................................526
22.7 Module Configuration ....................................................................................537
23 General-Purpose Input/Output Controller (GPIO) ............................. 539
23.1 Features ........................................................................................................539
23.2 Overview ........................................................................................................539
23.3 Block Diagram ...............................................................................................539
23.4 I/O Lines Description .....................................................................................540
23.5 Product Dependencies ..................................................................................540
23.6 Functional Description ...................................................................................541
23.7 User Interface ................................................................................................547
23.8 Module Configuration ....................................................................................572
24 Universal Synchronous Asynchronous Receiver Transmitter (USART)