AT32UC3A0256 Atmel Corporation, AT32UC3A0256 Datasheet - Page 265

• Manufacturer Part Number: AT32UC3A0256
• Manufacturer: Atmel Corporation

Specifications of AT32UC3A0256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 66 MHz
• Cpu: 32-bit AVR
• # Of Touch Channels: 32
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 109
• Ext Interrupts: 109
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device + OTG
• Spi: 6
• Twi (i2c): 1
• Uart: 4
• Ssc: 1
• Ethernet: 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
• Dac Channels: 2
• Dac Resolution (bits): 16
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 64
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.0-3.6 or (1.65-1.95+3.0-3.6)
• Operating Voltage (vcc): 3.0-3.6 or (1.65-1.95+3.0-3.6)
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 10
• Output Compare Channels: 16
• Input Capture Channels: 6
• Pwm Channels: 13
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

32058K AVR32-01/12
25.7.1.4
25.7.2
Transmitter Operations
Serial Clock Ratio Considerations
Figure 25-7. Receiver Clock Management
The Transmitter and the Receiver can be programmed to operate with the clock signals provided
on either the TX_CLOCK or RX_CLOCK pins. This allows the SSC to support many slave-mode
data transfers. In this case, the maximum clock speed allowed on the RX_CLOCK pin is:
In addition, the maximum clock speed allowed on the TX_CLOCK pin is:
A transmitted frame is triggered by a start event and can be followed by synchronization data
before data transmission.
The start event is configured by setting the Transmit Clock Mode Register (TCMR).
“25.7.4” on page 267.
The frame synchronization is configured setting the Transmit Frame Mode Register (TFMR).
See Section “25.7.5” on page 269.
To transmit data, the transmitter uses a shift register clocked by the transmitter clock signal and
the start mode selected in the TCMR. Data is written by the application to the THR register then
transferred to the shift register according to the data format selected.
When both the THR and the transmit shift register are empty, the status flag TXEMPTY is set in
SR. When the Transmit Holding register is transferred in the Transmit shift register, the status
flag TXRDY is set in SR and additional data can be loaded in the holding register.
Transmitter
RX_CLOCK (pin)
Divider
Clock
Clock
– Master Clock divided by 2 if Receiver Frame Synchro is input
– Master Clock divided by 3 if Receiver Frame Synchro is output
– Master Clock divided by 6 if Transmit Frame Synchro is input
– Master Clock divided by 2 if Transmit Frame Synchro is output
MUX
CKS
CKO
Controller
Tri-state
MUX
INV
CKI
Data Transfer
Controller
Tri-state
CKG
AT32UC3A
See Section
Receiver
Output
Clock
Clock
265