ATUC64L4U Atmel Corporation, ATUC64L4U Datasheet - Page 565

• Manufacturer Part Number: ATUC64L4U
• Manufacturer: Atmel Corporation

Specifications of ATUC64L4U

• Flash (kbytes): 64 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

23.8.2
23.8.2.1
32142A–12/2011
Operation
Bus Timing
Figure 23-4. Transfer Format
The TWIS has two modes of operation:
A master is a device which starts and stops a transfer and generates the TWCK clock. A slave is
assigned an address and responds to requests from the master. These modes are described in
the following chapters.
Figure 23-5. Typical Application Block Diagram
The Timing Register (TR) is used to control the timing of bus signals driven by the TWIS. TR
describes bus timings as a function of cycles of the prescaled CLK_TWIS. The clock prescaling
can be selected through TR.EXP.
TR has the following fields:
TLOWS: Prescaled clock cycles used to time SMBUS timeout T
• Slave transmitter mode
• Slave receiver mode
Rp: Pull up value as given by the I²C Standard
Host with
Interface
TWI
TWD
TWCK
TWD
TWCK
Start
Serial EEPROM
Atmel TWI
Slave 1
Address
R/W
f
Ack
PRESCALED
I²C RTC
Slave 2
Data
=
f
------------------------ -
2
CLK_TWIS
EXP
Controller
I²C LCD
Slave 3
ATUC64/128/256L3/4U
+
Ack
1
LOW:SEXT
Data
I²C Temp.
Sensor
Slave 4
.
Rp
Ack
Stop
Rp
VDD
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