.. zephyr:board:: nrf52840_blip

Overview

The Electronut Labs Blip 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)
Segger RTT (RTT Console)
:abbr:SPI (Serial Peripheral Interface)
:abbr:UART (Universal asynchronous receiver-transmitter)
:abbr:USB (Universal Serial Bus)
:abbr:WDT (Watchdog Timer)

More information about the board is available at https://github.com/electronut/ElectronutLabs-blip.

Hardware

Blip has two external oscillators. The frequency of the slow clock is 32.768 kHz. The frequency of the main clock is 32 MHz.

Supported Features

.. zephyr:board-supported-hw::

Connections and IOs

LED

LED1 (green) = P0.13
LED2 (red) = P0.14
LED3 (blue) = P0.15

Push buttons

BUTTON1 = SW1 = P1.07
Reset = SW5 = P0.18 (can be used as GPIO also)

UART

BMP does not support hardware flow control, so only RX/TX pins are connected.

TX = P0.6
RX = P0.8

I2C

I2C pins connected to onboard sensors:

SDA = P0.12
SCL = P0.11

SPI

SCK = P0.25
MOSI = P1.02
MISO = P0.24

MicroSD is connected to these pins, and CS pin is connected to P0.17.

Programming and Debugging

.. zephyr:board-supported-runners::

Applications for the nrf52840_blip board configuration can be built and flashed in the usual way (see :ref:build_an_application and :ref:application_run for more details); The onboard Black Magic Probe debugger presents itself as two USB-serial ports. On Linux, they may come up as /dev/ttyACM0 and /dev/ttyACM1. The first one of these (/dev/ttyACM0 here) is the debugger port. GDB can directly connect to this port without requiring a GDB server by specifying target external /dev/ttyACM0. The second port acts as a serial port, connected to the SoC.

Flashing

Applications are flashed and run as usual (see :ref:build_an_application and :ref:application_run for more details).

Here is an example for the :zephyr:code-sample:hello_world application.

First, run your favorite terminal program to listen for output.

.. code-block:: console

$ minicom -D <tty_device> -b 115200

Replace :code:<tty_device> with the serial port of Black Magic Probe. For example, under Linux, :code:/dev/ttyACM1.

Then build and flash the application in the usual way.

.. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: nrf52840_blip :goals: build flash

Debugging

Debug and attach configurations are available using Black Magic Probe, and ninja debug, or ninja attach (or with make) are available.

NOTE: You may need to press the reset button once after using ninja flash to start executing the code. (not required with debug or attach)

Testing the LEDs and buttons in the nRF52840 PDK

There are 2 samples that allow you to test that the buttons (switches) and LEDs on the board are working properly with Zephyr:

:zephyr:code-sample:blinky
:zephyr:code-sample:button

You can build and flash the examples to make sure Zephyr is running correctly on your board. The button and LED definitions can be found in :zephyr_file:boards/electronut/nrf52840_blip/nrf52840_blip.dts.

References

.. target-notes::

.. _Electronut Labs website: https://electronut.in .. _Store link: https://www.tindie.com/stores/ElectronutLabs/ .. _Blip website: https://github.com/electronut/ElectronutLabs-blip .. _Schematic: https://github.com/electronut/ElectronutLabs-blip/blob/master/blip_v0.3_schematic.pdf .. _Nordic Semiconductor Infocenter: http://infocenter.nordicsemi.com/ .. _Black Magic Probe website: https://github.com/blacksphere/blackmagic