Atmel SAM D21 Xplained Pro¶
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¶
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 |
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 |
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
1 2 3 4 | 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:
1 2 3 | 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
Arch Linux¶
With yaourt:
1 2 3 | 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.