circuitpython/atmel-samd

SAMD21x18

This port is intended to be a full featured MicroPython port for SAMD21x18 based development boards including the Arduino Zero, Adafruit Feather M0 and Adafruit M0 BLE.

Building

The Makefile has the ability to build for a SAMD21x18, and by default includes some start-up code and also enables a UART for communication. To build:

make CROSS=1

It will build for the Arduino Zero by default. You may change it by setting BOARD. For example:

make CROSS=1 BOARD=feather_m0_ble

Board names are the directory names in the boards folder.

Deploying

Arduino Bootloader

If your board has an existing Arduino bootloader on it then you can use bossac to flash MicroPython. First, activate the bootloader. On Adafruit Feathers you can double click the reset button and the #13 will fade in and out. Finally, run bossac:

tools/bossac_osx -e -w -v -b -R build-feather_m0_ble/firmware.bin

No Bootloader via GDB

This method works for loading MicroPython onto the Arduino Zero via the programming port rather than the native USB port.

Note: These instructions are tested on Mac OSX and will vary for different platforms.

openocd -f ~/Library/Arduino15/packages/arduino/hardware/samd/1.6.6/variants/arduino_zero/openocd_scripts/arduino_zero.cfg

In another terminal from micropython/atmel-samd:

arm-none-eabi-gdb build-arduino_zero/firmware.elf
(gdb) tar ext :3333
...
(gdb) load
...
(gdb) monitor reset init
...
(gdb) continue

Connecting

All boards are currently configured to work over USB rather than UART. To connect to it from OSX do something like this:

screen /dev/tty.usbmodem142422 115200

You may not see a prompt immediately because it doesn't know you connected. To get one either hit enter to get >>> or do CTRL-B to get the full header.