SAM R34 Xplained Pro Evaluation Kit

Overview

The SAM R34 Xplained Pro evaluation kit is ideal for evaluation and prototyping with the SAM R34 Cortex®-M0+ processor-based microcontrollers. The kit includes Atmel’s Embedded Debugger (EDBG), which provides a full debug interface without the need for additional hardware.

The SAMR34 and SAMR35 parts are produced as a System-in-Package (SiP), including both a SAML21 die, and a Semtech SX1276 LoRa radio die.

This board is also referred to as DM320111.

ATSAMR34-XPRO

Hardware

  • ATSAMR34J18 ARM Cortex-M0+ processor at 48 MHz

  • 32.768 kHz crystal oscillator

  • 256 KiB flash memory, 32 KiB of SRAM, 8KB Low Power SRAM

  • One yellow user LED

  • One mechanical user push button

  • One reset button

  • On-board USB based EDBG unit with serial console

Supported Features

The atsamr34_xpro board configuration supports the following hardware features:

Interface

Controller

Driver / Component

NVIC

on-chip

nested vector interrupt controller

Flash

on-chip

Can be used with LittleFS to store files

SYSTICK

on-chip

systick

WDT

on-chip

Watchdog

GPIO

on-chip

I/O ports

PWM

on-chip

Pulse Width Modulation

USART

on-chip

Serial ports

I2C

on-chip

I2C ports

SPI

on-chip

Serial Peripheral Interface ports

TRNG

on-chip

True Random Number Generator

The following hardware features are supported by Zephyr, but not yet fully supported by the SOC:

Interface

Controller

Driver / Component

LoRa Radio

on-chip

Internal SX1276 LoRa Radio

Other hardware features are not currently supported by Zephyr.

The default configuration can be found in the Kconfig boards/arm/atsamr34_xpro/atsamr34_xpro_defconfig.

Pin Mapping

The SAM R34 Xplained Pro evaluation kit has 3 GPIO controllers. These controllers are responsible for pin muxing, input/output, pull-up, etc.

For mode details please refer to SAM R34 Family Datasheet [1] and the SAM R34 Xplained Pro Schematic [2].

ATSAMR34-XPRO-pinout

Default Zephyr Peripheral Mapping:

  • SERCOM0 UART TX : PA04

  • SERCOM0 UART RX : PA05

  • SERCOM1 I2C SDA : PA16

  • SERCOM1 I2C SCL : PA17

  • SERCOM4 SPI MISO : PC19

  • SERCOM4 SPI MOSI : PB30

  • SERCOM4 SPI SCK : PC18

  • SERCOM4 GPIO CS : PB31

  • SERCOM5 SPI MISO : PB02

  • SERCOM5 SPI MOSI : PB22

  • SERCOM5 SPI SCK : PB23

  • SERCOM5 GPIO CS0 : PA23

  • SERCOM5 GPIO CS1 : PA14

  • USB DP : PA25

  • USB DM : PA24

  • GPIO/PWM LED0 : PA19

System Clock

The SAMR34 MCU is configured to use the 32.768 kHz external oscillator with the on-chip PLL generating the 48 MHz system clock.

Serial Port

The SAMR34 MCU has six SERCOM based USARTs with one configured as USART in this BSP. SERCOM0 is the default Zephyr console.

  • SERCOM0 115200 8n1 - connected to the onboard Atmel Embedded Debugger (EDBG)

PWM

The SAMR34 MCU has 3 TCC based PWM units with up to 4 outputs each and a period of 24 bits or 16 bits. If CONFIG_PWM_SAM0_TCC is enabled then LED0 is driven by TCC0 instead of by GPIO.

SPI Port

The SAMR34 MCU has 6 SERCOM based SPIs, with two configured as SPI in this BSP.

  • SERCOM4 - connected to the internal LoRa radio

  • SERCOM5 - connected to EXT1 and EXT3

Programming and Debugging

The SAM R34 Xplained Pro comes with a Atmel Embedded Debugger (EDBG). This provides a debug interface to the SAMR34 chip and is supported by OpenOCD.

Flashing

  1. Build the Zephyr kernel and the hello_world sample application:

    west build -b atsamr34_xpro samples/hello_world

  2. Connect the SAM R34 Xplained Pro to your host computer using the USB debug port.

  3. Run your favorite terminal program to listen for output. Under Linux the terminal should be /dev/ttyACM0. For example:

    $ picocom -b 115200 /dev/ttyACM0

    • Speed: 115200

    • Data: 8 bits

    • Parity: None

    • Stop bits: 1

  4. To flash an image:

    west build -b atsamr34_xpro samples/hello_world
west flash

    You should see “Hello World! atsamr34_xpro” in your terminal.

References