Data Sheet

432
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181G–SAM-D21_Datasheet–09/2015
24. SERCOM – Serial Communication Interface
24.1 Overview
The serial communication interface (SERCOM) can be configured to support a number of modes; I
2
C, SPI, and USART.
Once configured and enabled, all SERCOM resources are dedicated to the selected mode.
The SERCOM serial engine consists of
a transmitter and receiver, baud-rate generator and address matching
functionality. It can be configured to use the internal generic clock or an external clock, making operation in all sleep
modes possible.
24.2 Features
z Combined interface configurable as one of the following:
z I
2
C – Two-wire serial interface
z SMBus
™
compatible.
z SPI – Serial peripheral interface
z USART – Universal synchronous and asynchronous serial receiver and transmitter
z Single transmit buffer and double receive buffer
z Baud-rate generator
z Address match/mask logic
z Operational in all sleep modes
z Can be used with DMA
24.3 Block Diagram
Figure 24-1. SERCOM Block Diagram
24.4 Signal Description
See the respective SERCOM mode chapters for details:
z “SERCOM USART – SERCOM Universal Synchronous and Asynchronous Receiver and Transmitter” on page
440
z “SERCOM SPI – SERCOM Serial Peripheral Interface” on page 478
z “SERCOM I2C – SERCOM Inter-Integrated Circuit” on page 511
TX/RX DATA
CONTROL/STATUS
Mode n
SERCOM
BAUD/ADDR
Transmitter
Register Interface
Serial Engine
Receiver
Mode 0
Mode 1
Baud Rate
Generator
Address
Match
Mode Specific
PAD[3:0]