ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 621

• Manufacturer Part Number: ATSAM3U-EK
• Description: KIT EVAL FOR AT91SAM3U CORTEX
• Manufacturer: Atmel
• Type: MCUr

Specifications of ATSAM3U-EK

• Contents: Board
• Processor To Be Evaluated: SAM3U
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3 V
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex - M3
• Silicon Core Number: SAM3U4E
• Silicon Family Name: SAM3U
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT91SAM3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

33. Two-wire Interface (TWI)
33.1
33.2
6430D–ATARM–25-Mar-11
Description
List of Abbreviations
The Atmel Two-wire Interface (TWI) interconnects components on a unique two-wire bus, made
up of one clock line and one data line with speeds of up to 400 Kbits per second, based on a
byte-oriented transfer format. It can be used with any Atmel Two-wire Interface bus Serial
EEPROM and I²C compatible device such as Real Time Clock (RTC), Dot Matrix/Graphic LCD
Controllers and Temperature Sensor, to name but a few. The TWI is programmable as a master
or a slave with sequential or single-byte access. Multiple master capability is supported. 20
Arbitration of the bus is performed internally and puts the TWI in slave mode automatically if the
bus arbitration is lost.
A configurable baud rate generator permits the output data rate to be adapted to a wide range of
core clock frequencies.
Below,
a full I2C compatible device.
Table 33-1.
Note:
Table 33-2.
I2C Standard
Standard Mode Speed (100 KHz)
Fast Mode Speed (400 KHz)
7 or 10 bits Slave Addressing
START BYTE
Repeated Start (Sr) Condition
ACK and NACK Management
Slope control and input filtering (Fast mode)
Clock stretching
Multi Master Capability
Abbreviation
TWI
A
NA
P
S
Sr
SADR
Table 33-1
1. START + b000000001 + Ack + Sr
(1)
Atmel TWI compatibility with I2C Standard
Abbreviations
lists the compatibility level of the Atmel Two-wire Interface in Master Mode and
Description
Two-wire Interface
Acknowledge
Non Acknowledge
Stop
Start
Repeated Start
Slave Address
Atmel TWI
Supported
Supported
Supported
Not Supported
Supported
Supported
Not Supported
Supported
Supported
SAM3U Series
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