Datasheet

Bits 2:1 – UCSZmn: Character Size [n = 1:0]
The UCSZm1:0 bits combined with the UCSZm2 bit in UCSRmB sets the number of data bits (Character
Size) in a frame the Receiver and Transmitter use.
Table 25-11 UCSZ Bits Settings
UCSZm2 UCSZm1 UCSZm0 Character Size
0 0 0 5-bit
0 0 1 6-bit
0 1 0 7-bit
0 1 1 8-bit
1 0 0 Reserved
1 0 1 Reserved
1 1 0 Reserved
1 1 1 9-bit
Bit 0 – UCPOLm: Clock Polarity
This bit is used for synchronous mode only. Write this bit to zero when Asynchronous mode is used. The
UCPOLm bit sets the relationship between data output change and data input sample, and the
synchronous clock (XCKm).
Table 25-12 UCPOLm Bit Settings
UCPOLm Transmitted Data Changed
(Output of TxDm Pin)
Received Data Sampled
(Input on RxDm Pin)
0 Rising XCKm Edge Falling XCKm Edge
1 Falling XCKm Edge Rising XCKm Edge
Atmel ATmega64A [DATASHEET]
Atmel-8160E-ATmega64A_Datasheet_Complete-09/2015
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