.. zephyr:board:: promicro_nrf52840

More of a board type than a unique board, It is based on Nice!Nano. Also referred to as Pro Micro, Promicro, SuperMini nRF52840 boards.

Overview

The hardware provides support for the Nordic Semiconductor nRF52840 ARM Cortex-M4F CPU and the following devices:

• :abbr:ADC (Analog to Digital Converter)
• CLOCK
• FLASH
• :abbr:GPIO (General Purpose Input Output)
• :abbr:I2C (Inter-Integrated Circuit)
• :abbr:MPU (Memory Protection Unit)
• :abbr:NVIC (Nested Vectored Interrupt Controller)
• :abbr:PWM (Pulse Width Modulation)
• RADIO (Bluetooth Low Energy and 802.15.4)
• :abbr:RTC (nRF RTC System Clock)
• :abbr:SPI (Serial Peripheral Interface)
• :abbr:UART (Universal asynchronous receiver-transmitter)
• :abbr:USB (Universal Serial Bus)
• :abbr:WDT (Watchdog Timer)

More information about the original board can be found at the Nice!Nano website_.

Information about clones can be found at Clone Wiki_.

Pinout and Schematic are available in the Nice!Nano Documentation_

Supported Features

.. zephyr:board-supported-hw::

Connections and IOs

LED

• LED0 = P0.15, can be any color.

Programming and Debugging

.. zephyr:board-supported-runners::

Applications for the promicro_nrf52840/nrf52840 board target can be built in the usual way (see :ref:build_an_application for more details).

Flashing

The board is factory-programmed with Adafruit's UF2 bootloader

#. Reset the board into the bootloader by bridging ground and RST 2 times quickly

The status LED should start a fade pattern, signalling the bootloader is running.

#. Compile a Zephyr application; we'll use :zephyr:code-sample:blinky.

.. zephyr-app-commands:: :app: zephyr/samples/basic/blinky :board: promicro_nrf52840/nrf52840/uf2 :goals: build

#. Flash it onto the board. You may need to mount the device.

.. code-block:: console

  west flash

When this command exits, observe the red LED on the board blinking,

Debugging

You may debug this board using the broken out pads on the back. PyOCD and openOCD can be used to flash and debug this board.

Recovery

In case of a error resulting in a board's bootloader becoming inaccessible, it is possible to flash anything directly using openOCD:

#. Setup OpenOCD correctly, here for WCH linkE in ARM mode:

.. code-block:: console

  openocd -f interface/cmsis-dap.cfg -f target/nrf52.cfg

Note interface and target folders are from openOCD's tcl folder.

#. Connect to openOCD, for example with telnet or GDB:

.. code-block:: console

  telnet localhost 4444

.. code-block:: console

  target extended-remote localhost:3333

#. Erase flash:

.. code-block:: console

  reset halt
  nrf5 mass_erase

or

.. code-block:: console

  mon reset halt
  mon nrf5 mass_erase

#. Flash Bootloader

.. code-block:: console

  flash write_image erase nice_nano_bootloader-0.9.2_s140_6.1.1.hex

or

.. code-block:: console

  mon flash write_image erase nice_nano_bootloader-0.9.2_s140_6.1.1.hex

References

.. target-notes::

.. _Nice!Nano website: https://nicekeyboards.com/docs/nice-nano/ .. _Clone Wiki: https://github.com/joric/nrfmicro/wiki/Alternatives .. _Nice!Nano Documentation: https://nicekeyboards.com/docs/nice-nano/pinout-schematic