AT32UC3A464 Atmel Corporation, AT32UC3A464 Datasheet - Page 481

• Manufacturer Part Number: AT32UC3A464
• Manufacturer: Atmel Corporation

Specifications of AT32UC3A464

• Flash (kbytes): 64 Kbytes
• Pin Count: 100
• Max. Operating Frequency: 66 MHz
• Cpu: 32-bit AVR
• Hardware Qtouch Acquisition: No
• Usb Transceiver: 1
• Usb Speed: Hi-Speed
• Usb Interface: Device + OTG
• Spi: 6
• Twi (i2c): 2
• Uart: 4
• Ssc: 1
• Sd / Emmc: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 128
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.0 to 3.6
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Figure 23-9. Master Read with Multiple Data Bytes
32072G–11/2011
SR.IDLE
RXRDY
TWD
NBYTES set to m
Write START +
S
STOP bit
DADR
Writing CMDR with START=STOP=1 and NBYTES=0 will generate a transmission with no data
bytes, ie START, DADR+R, STOP
The TWI transfers require the master to acknowledge each received data byte. During the
acknowledge clock pulse (9th pulse), the slave releases the data line (HIGH), enabling the mas-
ter to pull it down in order to generate the acknowledge. All data bytes except the last are
acknowledged by the master. Not acknowledging the last byte informs the slave that the transfer
is finished.
RXRDY is used as Receive Ready for the Peripheral DMA Controller receive channel.
Figure 23-8. Master Read with One Data Byte
SR.IDLE
1. Wait until RHR is empty, stretching low period of TWCK. SR.RXRDY indicates the state
2. Release TWCK generating a clock that the slave uses to transmit a data byte.
3. Place the received data byte in RHR, set RXRDY.
4. If NBYTES=0, generate a NAK after the data byte, otherwise generate an ACK.
5. Decrement NBYTES
6. If (NBYTES==0) and STOP=1, transmit STOP condition.
RXRDY
TWD
of RHR. Software or the Peripheral DMA Controller must read any data byte present in
RHR.
R
NBYTES set to 1
Write START &
S
STOP bit
A
DADR
DATAn
R
Read RHR
DATAn
A
A
DATAn+1
DATA
DATAn+m-2
Read RHR
DATAn+m-1
N
Read RHR
P
DATAn+m-1
Read RHR
A
DATAn+m
When NBYTES=0
Send STOP
N
Read RHR
DATAn+m
P
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