ATmega1281R231 Atmel Corporation, ATmega1281R231 Datasheet - Page 240

• Manufacturer Part Number: ATmega1281R231
• Manufacturer: Atmel Corporation

Specifications of ATmega1281R231

• Flash (kbytes): 128 Kbytes
• Max. Operating Frequency: 16 MHz
• Max I/o Pins: 54
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Crypto Engine: AES
• Sram (kbytes): 8
• Eeprom (bytes): 4096
• Operating Voltage (vcc): 1.8 to 3.6
• Timers: 6
• Frequency Band: 2.4 GHz
• Max Data Rate (mb/s): 2
• Antenna Diversity: Yes
• External Pa Control: Yes
• Power Output (dbm): 3
• Receiver Sensitivity (dbm): -101
• Receive Current Consumption (ma): 13.2
• Transmit Current Consumption (ma): 14.4
• Link Budget (dbm): 104

23.6.5
2549N–AVR–05/11
UBRRnL and UBRRnH – USART MSPIM Baud Rate Registers
• Bit 2 - UDORDn: Data Order
When set to one the LSB of the data word is transmitted first. When set to zero the MSB of the
data word is transmitted first. Refer to
• Bit 1 - UCPHAn: Clock Phase
The UCPHAn bit setting determine if data is sampled on the leasing edge (first) or tailing (last)
edge of XCKn. Refer to
• Bit 0 - UCPOLn: Clock Polarity
The UCPOLn bit sets the polarity of the XCKn clock. The combination of the UCPOLn and
UCPHAn bit settings determine the timing of the data transfer. Refer to
Timing” on page 233
The function and bit description of the baud rate registers in MSPI mode is identical to normal
USART operation.
Table 23-4.
USART_MSPIM
XCKn
RxDn
TxDn
(N/A)
Comparison of USART in MSPIM mode and SPI pins.
See “UBRRnL and UBRRnH – USART Baud Rate Registers” on page 227.
for details.
“SPI Data Modes and Timing” on page 233
ATmega640/1280/1281/2560/2561
MOSI
MISO
SCK
SPI
SS
“SPI Data Modes and Timing” on page 233
Not supported by USART in MSPIM
(Functionally identical)
Master Out only
Master In only
for details.
Comment
“SPI Data Modes and
for details.
240