Atmel SAM W25 Xplained Pro, User Manual

Page: 10 / 16

Atmel SAM W25 Xplained Pro [USER GUIDE]
42463A-MCU-06/2015
10
4. Hardware User Guide
4.1 Connectors
This chapter describes the implementation of the relevant connectors and headers on SAM W25 Xplained
Pro and their connection to the ATSAMW25H18-MR510PB. 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 W25 Xplained Pro header EXT1 offers access to the I/O of the integrated 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 W25
pin
Function Shared functionality
1 [ID] - - Communication line to ID chip
on extension board.
2 [GND] - - GND
3 [ADC(+)] PA02 AIN[0]
4 [ADC(-)] PA03 AIN[1]
5 [GPIO1] PB02 GPIO
6 [GPIO2] PB03 GPIO
7 [PWM(+)] PA10 TCC0/WO[2]
8 [PWM(-)] PA11 TCC0/WO[3]
9 [IRQ/GPIO] PA20 EXTINT[4]
10 [SPI_SS_B/GPIO] PA21 GPIO/CS for SPI
11 [TWI_SDA] PA08 SERCOM0 PAD[0] I²C SDA EDBG
12 [TWI_SCL] PA09 SERCOM0 PAD[1] I²C SCL EDBG
13 [USART_RX] PB11 SERCOM4 PAD[3] UART RX EDBG
14 [USART_TX] PB10 SERCOM4 PAD[2] UART TX EDBG
15 [SPI_SS_A] PA17 SERCOM1 PAD[1] SPI SS
16 [SPI_MOSI] PA18 SERCOM1 PAD[2] SPI MOSI EDBG and Serial Flash
17 [SPI_MISO] PA16 SERCOM1 PAD[0] SPI MISO EDBG and Serial Flash
18 [SPI_SCK] PA19 SERCOM1 PAD[3] SPI SCK EDBG and Serial Flash
19 [GND] - - GND
20 [VCC] - - VCC
4.2 Peripherals
4.2.1 Crystal
The SAM W25 Xplained Pro kit contains two crystals; One is used as clock source for the SAM W25 device
and the second one is used as clock for EDBG. The crystal connected with SAM W25 has a cut-strap next
to it that can be used to measure the oscillator safety factor. This is done by cutting the strap and adding a
resistor across the strap. More information about oscillator allowance and safety factor can be found in appnote
AVR4100
1
.
Table 4-2. External 32.768kHz Crystals
Pin on SAM W25 Function
PA00 XIN32
1
http://www.atmel.com/images/doc8333.pdf