User manual

AVR364
11
8377B-AVR-11/11
6.5 Board controller
The Atmel AT32UC3B1256 board controller and the Atmel ATmega1284P are
connected through TWI, SPI, and USART interfaces. All interfaces can be used to
communicate between the devices, but only the USART is implemented by default on
the board controller.
Table 6-2. ATmega1284P and board controller communication interface.
Interface ATmega1284P pin Atmel AT32UC3B1256 pin
UART RX
(1)
PD2 PA24
UART TX
(1)
PD3 PA23
TWI SCL PC0 PA09
TWI SDA PC1 PA10
SPI SS
(2)
PB4 PA16
SPI MOSI
(2)
PB5 PA14
SPI MISO
(2)
PB6 PA25
SPI SCK
(2)
PB7 PA17
Notes: 1. This represents the RX and TX on the ATmega1284P. The RX is connected to
TX on the other device, and vice versa.
2. These signals can be disconnected from the board controller by cutting the cut-
straps marked SPI on the bottom side of the board.