Support for the Atmel SAM D21 Xplained Pro board. More...

Detailed Description

Support for the Atmel SAM D21 Xplained Pro board.

Overview

The SAMD21 Xplained Pro is an ultra-low power evaluation board by Atmel featuring an ATSAMD21J18A SoC. The SoC includes a SAMD21 ARM Cortex-M0+ micro- controller. For programming the MCU comes with 32Kb of RAM and 256Kb of flash memory.

The samd21-xpro is available from various hardware vendors for ~30USD (as of 2017May).

Hardware

samd21-xpro image

MCU

MCU	ATSAMD21J18A
Family	ARM Cortex-M0+
Vendor	Atmel
RAM	32Kb
Flash	256Kb
Frequency	up to 48MHz
FPU	no
Timers	5 (16-bit)
ADCs	1x 12-bit (20 channels)
UARTs	max 6 (shared with SPI and I2C)
SPIs	max 6 (see UART)
I2Cs	max 6 (see UART)
Vcc	1.62V - 3.63V
Datasheet	Datasheet
Board Manual	Board Manual

User Interface

1 User button and 1 LED:

Device	PIN
LED0	PB30
SW0 (button)	PA15

Implementation Status

Device	ID	Supported	Comments
MCU	samd21	partly	DFLL clock not implemented
Low-level driver	GPIO	yes
	ADC	yes
	PWM	yes
	UART	yes
	I2C	unknown
	SPI	yes
	USB	no
	RTT	yes
	RTC	yes
	RNG	unknown
	Timer	yes

Flashing the device

Connect the device to your Micro-USB cable using the port labeled as DEBUG USB.

The standard method for flashing RIOT to the samd21-xpro is using OpenOCD.

Refer to https://github.com/RIOT-OS/RIOT/wiki/OpenOCD for general instructions on building OpenOCD and make sure "cmsis-dap" and "hidapi-libusb" are enabled.

On Linux you will have to add a udev rule for hidraw, like

bash
echo 'KERNEL=="hidraw*", SUBSYSTEM=="hidraw", MODE="0664", GROUP="plugdev"' \
    | sudo tee -a /etc/udev/rules.d/99-usb.rules
sudo service udev restart

Arch Linux

With yaourt:

yaourt -S hidapi-git
yaourt -S openocd-git
# edit PKGBUILD, add "cmsis-dap hidapi-libusb" to "_features"

Ubuntu

Although this refers to setting up the SAMR21, this guide is still very helpful to understanding how to set up a solid RIOT development environment for the SAMD21: http://watr.li/samr21-dev-setup-ubuntu.html

Supported Toolchains

For using the samd21-xpro board we strongly recommend the usage of the GNU Tools for ARM Embedded Processors toolchain.

Known Issues / Problems

Files
file	board.h
	Board specific definitions for the Atmel SAM D21 Xplained Pro board.

file	gpio_params.h
	Board specific configuration of direct mapped GPIOs.

file	periph_conf.h
	Configuration of CPU peripherals for the Atmel SAM D21 Xplained Pro board.