zephyr/boards/arduino/zero/doc/index.rst

167 lines
5.1 KiB
ReStructuredText
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

.. _arduino_zero:
Arduino/Genuino Zero
####################
Overview
********
The Arduino Zero is a maker-friendly development board with
Atmels Embedded Debugger (EDBG), which provides a full
debug interface without the need for additional hardware.
.. image:: img/arduino_zero.jpg
:align: center
:alt: Arduino Zero
Hardware
********
- ATSAMD21G18A ARM Cortex-M0+ processor at 48 MHz
- 32.768 kHz crystal oscillator
- 256 KiB flash memory and 32 KiB of RAM
- 3 user LEDs
- One reset button
- On-board USB based EDBG unit with serial console
- Native USB port
Supported Features
==================
The arduino_zero 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 |
+-----------+------------+------------------------------------------+
| SPI | on-chip | Serial Peripheral Interface ports |
+-----------+------------+------------------------------------------+
| USB | on-chip | USB device |
+-----------+------------+------------------------------------------+
| DAC | on-chip | Digital to analogue converter |
+-----------+------------+------------------------------------------+
Other hardware features are not currently supported by Zephyr.
The default configuration can be found in the Kconfig
:zephyr_file:`boards/arduino/zero/arduino_zero_defconfig`.
Connections and IOs
===================
The `Arduino store`_ has detailed information about board
connections. Download the `Arduino Zero Schematic`_ for more detail.
System Clock
============
The SAMD21 MCU is configured to use the 32.768 kHz external oscillator
with the on-chip PLL generating the 48 MHz system clock. The internal
APB and GCLK unit are set up in the same way as the upstream Arduino
libraries.
Serial Port
===========
The SAMD21 MCU has 6 SERCOM based USARTs. One of the USARTs
(SERCOM5) is connected to the onboard Atmel Embedded Debugger (EDBG).
SERCOM0 is available on the D0/D1 pins.
PWM
===
The SAMD21 MCU has 3 TCC based PWM units with up to 4 outputs each and a period
of 24 bits or 16 bits. If :code:`CONFIG_PWM_SAM0_TCC` is enabled then LED0 is
driven by TCC2 instead of by GPIO.
SPI Port
========
The SAMD21 MCU has 6 SERCOM based SPIs. On the Arduino Zero, SERCOM4
is available on the 6 pin connector at the edge of the board.
USB Device Port
===============
The SAMD21 MCU has a USB device port that can be used to communicate
with a host PC. See the :ref:`usb-samples` sample applications for
more, such as the :zephyr:code-sample:`usb-cdc-acm` sample which sets up a virtual
serial port that echos characters back to the host PC.
DAC
===
The SAMD21 MCU has a single channel DAC with 10 bits of resolution. On the
Arduino Zero, the DAC is available on pin A0.
Programming and Debugging
*************************
The Arduino Zero comes with a Atmel Embedded Debugger (EDBG). This
provides a debug interface to the SAMD21 chip and is supported by
OpenOCD.
Flashing
========
#. Build the Zephyr kernel and the :ref:`hello_world` sample application:
.. zephyr-app-commands::
:zephyr-app: samples/hello_world
:board: arduino_zero
:goals: build
:compact:
#. Connect the Arduino Zero to your host computer using the USB debug
port.
#. Run your favorite terminal program to listen for output. Under Linux the
terminal should be :code:`/dev/ttyACM0`. For example:
.. code-block:: console
$ minicom -D /dev/ttyACM0 -o
The -o option tells minicom not to send the modem initialization
string. Connection should be configured as follows:
- Speed: 115200
- Data: 8 bits
- Parity: None
- Stop bits: 1
#. To flash an image:
.. zephyr-app-commands::
:zephyr-app: samples/hello_world
:board: arduino_zero
:goals: flash
:compact:
You should see "Hello World! arduino_zero" in your terminal.
References
**********
.. target-notes::
.. _Arduino Store:
https://store.arduino.cc/genuino-zero
.. _Arduino Zero Schematic:
https://www.arduino.cc/en/uploads/Main/Zero_V1.0.pdf