158
7647H–AVR–03/12
Atmel ATmega16/32/64/M1/C1
15. Serial Peripheral Interface – SPI
The Serial Peripheral Interface (SPI) allows high-speed synchronous data transfer between the
ATmega16/32/64/M1/C1 and peripheral devices or between several AVR devices.
The ATmega16/32/64/M1/C1 SPI includes the following features:
15.1 Features
• Full-duplex, Three-wire Synchronous Data Transfer
• Master or Slave Operation
• LSB First or MSB First Data Transfer
• Seven Programmable Bit Rates
• End of Transmission Interrupt Flag
• Write Collision Flag Protection
• Wake-up from Idle Mode
• Double Speed (CK/2) Master SPI Mode
Figure 15-1. SPI Block Diagram
(1)
Note: 1. Refer to Figure 1-1 on page 3, and Table 9-3 on page 69 for SPI pin placement.
SPI2X
SPI2X
DIVIDER
/2/4/8/16/32/64/128
clk
IO
MISO
MISO
_A
MOSI
MOSI
_A
SCK
SCK
_A
SS
SS_A
SPIPS