61
ATmega103(L)
0945G–09/01
SPI Data Register – SPDR
The SPI Data Register is a read/write register used for data transfer between the regis-
ter file and the SPI Shift Register. Writing to the register initiates data transmission.
Reading the register causes the Shift Register Receive buffer to be read.
Bit
7
6
5
4
3
2
1
0
$0F ($2F)
MSB
LSB
SPDR
Read/Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Initial Value
X
X
X
X
X
X
X
X
Undefined