User Manual

Atmel SAM R21 Xplained Pro [USER GUIDE]
42243B-MCU-06/2014
10
4. Hardware User Guide
4.1 Connectors
This chapter describes the implementation of the relevant connectors and headers on SAM R21 Xplained Pro
and their connection to the ATSAMR21G18A. The tables of connections in this chapter also describes which
signals are shared between the headers and on-board functionality.
4.1.1 I/O Extension Headers
The SAM R21 Xplained Pro headers EXT1 and EXT3 offer access to the I/O of the microcontroller in order
to expand the board e.g. by connecting extensions to the board. These headers all comply with the standard
extension header specified in Xplained Pro Standard Extension Header on page 7. All headers have a pitch of
2.54mm.
Table 4-1. Extension Header EXT1
Pin on EXT1 SAM R21 pin Function Shared functionality
1 [ID] - Communication line to ID chip
on extension board
2 [GND] - GND
3 [ADC(+)] PA06 AIN[6]
4 [ADC(-)] PA07 AIN[7]
5 [GPIO1] PA13 GPIO
6 [GPIO2] PA28 GPIO
7 [PWM(+)] PA18 TCC0 / WO[2]
8 [PWM(-)] PA19 TCC0 / WO[3]
9 [IRQ/GPIO] PA22 EXTINT[6]
10 [SPI_SS_B/GPIO] PA23 GPIO
11 [TWI_SDA] PA16 SERCOM1 PAD[0] I²C SDA EXT3 and EDBG
12 [TWI_SCL] PA17 SERCOM1 PAD[1] I²C SCL EXT3 and EDBG
13 [USART_RX] PA05 SERCOM0 PAD[1] UART RX EDBG
14 [USART_TX] PA04 SERCOM0 PAD[0] UART TX EDBG
15 [SPI_SS_A] PB03 SERCOM5 PAD[1] SPI SS
16 [SPI_MOSI] PB22 SERCOM5 PAD[2] SPI MOSI EXT3 and EDBG
17 [SPI_MISO] PB02 SERCOM5 PAD[0] SPI MISO EXT3 and EDBG
18 [SPI_SCK] PB23 SERCOM5 PAD[3] SPI SCK EXT3 and EDBG
19 [GND] - GND
20 [VCC] - VCC
Table 4-2. Extension Header EXT3
Pin on EXT3 SAM R21 pin Function Shared functionality
1 [ID] - Communication line to ID chip
on extension board
2 [GND] - GND
3 [ADC(+)] - -
4 [ADC(-)] - -
5 [GPIO1] PA15 GPIO
6 [GPIO2] -
7 [PWM(+)] -
8 [PWM(-)] -
9 [IRQ/GPIO] -