ATMEGA644PV ATMEL [ATMEL Corporation], ATMEGA644PV Datasheet - Page 168

• Manufacturer Part Number: ATMEGA644PV
• Description: 8-bit Microcontroller with 16/32/64K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

16.5.3
168
ATmega164P/324P/644P
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
0x2E (0x4E)
Read/Write
Initial Value
MSB
R/W
7
X
R/W
6
X
R/W
5
X
R/W
4
X
R/W
X
3
R/W
X
2
R/W
X
1
LSB
R/W
X
0
8011D–AVR–02/07
Undefined
SPDR