ATUC128L4U Atmel Corporation, ATUC128L4U Datasheet - Page 531

• Manufacturer Part Number: ATUC128L4U
• Manufacturer: Atmel Corporation

Specifications of ATUC128L4U

• Flash (kbytes): 128 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 50 MHz
• Cpu: 32-bit AVR
• # Of Touch Channels: 17
• Hardware Qtouch Acquisition: Yes
• Max I/o Pins: 36
• Ext Interrupts: 36
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 2
• Uart: 4
• Lin: 4
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 12
• Adc Speed (ksps): 460
• Analog Comparators: 8
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 16
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.62 to 3.6
• Operating Voltage (vcc): 1.62 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 6
• Output Compare Channels: 18
• Input Capture Channels: 12
• Pwm Channels: 35
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

22.8
22.8.1
22.8.2
32142A–12/2011
Functional Description
Transfer Format
Operation
The data put on the TWD line must be 8 bits long. Data is transferred MSB first; each byte must
be followed by an acknowledgement. The number of bytes per transfer is unlimited (see
22-4).
Each transfer begins with a START condition and terminates with a STOP condition (see
22-4).
Figure 22-3.
Figure 22-4. Transfer Format
The TWIM has two modes of operation:
The master is the device which starts and stops a transfer and generates the TWCK clock.
These modes are described in the following chapters.
• A high-to-low transition on the TWD line while TWCK is high defines the START condition.
• A low-to-high transition on the TWD line while TWCK is high defines a STOP condition.
• Master transmitter mode
• Master receiver mode
TWD
TWCK
START and STOP Conditions
Start
Address
TWCK
TWD
R/W
Start
Ack
Data
ATUC64/128/256L3/4U
Ack
Data
Stop
Ack
Stop
Figure
Figure
531