
103
8024A–AVR–04/08
ATmega8HVA/16HVA
18.5.3
SPDR – SPI Data Register
The SPI Data Register is a read/write register used for data transfer between the Register File
and the SPI Shift Register. Writing to the register initiates data transmission. Reading the regis-
ter causes the Shift Register Receive buffer to be read.
Bit
76543
210
MSB
LSB
SPDR
Read/Write
R/W
Initial Value
XXXXXXXX
Undefined