SAM7SE256 Atmel Corporation, SAM7SE256 Datasheet - Page 349

• Manufacturer Part Number: SAM7SE256
• Manufacturer: Atmel Corporation

Specifications of SAM7SE256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 48 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 88
• Ext Interrupts: 88
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

32. Two Wire Interface (TWI)
32.1
32.2
6222F–ATARM–14-Jan-11
Overview
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. Arbitra-
tion 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 32-1.
Note:
Table 32-2.
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
Abbreviation
TWI
A
NA
P
S
Sr
SADR
ADR
R
W
Table 32-1
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
Any address except SADR
Read
Write
Atmel TWI
Supported
Supported
Supported
Not Supported
Supported
Supported
Not Supported
Supported
SAM7SE512/256/32
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