Electronut Labs Blip

Overview

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

  • ADC
  • CLOCK
  • FLASH
  • GPIO
  • I2C
  • MPU
  • NVIC
  • PWM
  • RADIO (Bluetooth Low Energy and 802.15.4)
  • RTC
  • Segger RTT (RTT Console)
  • SPI
  • UART
  • USB
  • WDT
Electronut Labs Blip

Electronut Labs Blip (Credit: Electronut Labs)

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

The nrf52840_blip board configuration supports the following hardware features currently:

Interface Controller Driver/Component
ADC on-chip adc
CLOCK on-chip clock_control
FLASH on-chip flash
GPIO on-chip gpio
I2C(M) on-chip i2c
MPU on-chip arch/arm
NVIC on-chip arch/arm
PWM on-chip pwm
RADIO on-chip Bluetooth, ieee802154
RTC on-chip system clock
RTT Segger console
SPI(M/S) on-chip spi
UART on-chip serial
USB on-chip usb
WDT on-chip watchdog

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

Applications for the nrf52840_blip board configuration can be built and flashed in the usual way (see Build an Application and Run an Application 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 Build an Application and Run an Application for more details).

Here is an example for the Hello World application.

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

$ minicom -D <tty_device> -b 115200

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

Then build and flash the application in the usual way.

Using west:

# From the root of the zephyr repository
west build -b nrf52840_blip samples/hello_world
west flash

Using CMake and ninja:

# From the root of the zephyr repository
# Use cmake to configure a Ninja-based buildsystem:
cmake -B build -GNinja -DBOARD=nrf52840_blip samples/hello_world

# Now run ninja on the generated build system:
ninja -C build
ninja -C 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:

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 boards/arm/nrf52840_blip/nrf52840_blip.dts.

References