4.6 Extension Header Area

The marked area on the grid I7 to R8 can be used for strapping in an Xplained Pro extension header or a 10-pin legacy Xplained/RZ600 header.

The SPI bus signals are available close to the header at row J and K, enabling easy connection to header pin 15 to 18.

Using pins 11 to 20 enables connection of the 10-pin legacy header used on the RZ600 wireless modules and the 10-pin Xplained sensor modules.

The general bus connections for an Xplained Pro Extension board are indicated in the table below. Detailed wiring can be found in the selected extension board documentation.

Table 4-9. Extension Header Typical Signals
Pin	Signal Name	Signal Description
1	ID	Communication line to the ID chip on the Xplained extension board
2	GND	Ground
3	ADC(+)	Analog-to-Digital converter, alternatively positive part of differential ADC
4	ADC(-)	Analog-to-Digital converter, alternatively negative part of differential ADC
5	GPIO1	General purpose I/O
6	GPIO2	General purpose I/O
7	PWM(+)	Pulse-Width Modulation, alternatively positive part of differential PWM
8	PWM(-)	Pulse-Width Modulation, alternatively negative part of differential PWM
9	IRQ/GPIO	Interrupt request line and/or general purpose I/O
10	SPI_SS_B/ GPIO	Slave B select for SPI and/or general purpose I/O
11	I2C_SDA	Data line for I²C interface
12	I2C_SCL	Clock line for I²C interface
13	UART_RX	Receiver line of ATmega328P USART
14	UART_TX	Transmitter line of ATmega328P USART
15	SPI_SS_A	Slave A select for SPI
16	SPI_MOSI	Master out slave in line of serial peripheral interface
17	SPI_MISO	Master in slave out line of serial peripheral interface
18	SPI_SCK	Clock for serial peripheral interface
19	GND	Ground
20	VCC	Power for extension board