index.rst

CX1825 nRF52840

Overview

Croxel's CX1825 Bluetooth Prototyping board [1] 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:`USB (Universal Serial Bus)`
• :abbr:`WDT (Watchdog Timer)`

Croxel's CX1825 Bluetooth Prototyping board (Credit: Croxel)

Hardware

• Ezurio's BL654 (nRF52840 ARM Cortex-M4F processor at 64MHz)
• 1 MB flash memory and 256 KB of SRAM
• Coin-cell retainer for Lithium coincell batteries
• 2 Discrete LEDs (Red and Green)
• User Button
• Reset Button
• Accelerometer (LIS3DH)
• Ambient & RGB Light and Proximity Sensor (APDS9960)
• Temperature and Humidity Sensor (HTS221)
• Barometric Pressure sensor (LPS22H)
• Hall Effect Switch (MLX90248)
• RGB LED with Charge-Pump driver (LPS5521)
• Digital Microphone
• Beeper
• QWIIC connector supporting expansion for I2C devices
• USB Connector for data and power
• 16-pin Expansion connector
• SWD Connector

Supported Features

• Discrete LEDs (red and green)
• Buttons (User and Reset)
• Sensors (Accelerometer, Light, Temperature and Humidity, Pressure and Hall-Effect sensors)
• Beeper
• Radio (Bluetooth, IEEE 802.15.4)
• SOC peripherals (ADC, Clock, Flash, GPIO, I2C, MPU, NVIC, PWM, Radio, RTC, SPI, USB, WDT)

Future Feature Support

• RGB LED (Charge-Pump driver not implemented)
• Microphone

Connections and IOs

Croxel's CX1825 Bluetooth Prototyping board has detailed information about the board (schematic [2])

LEDs

• LED1 (red) = P0.8
• LED2 (green) = P0.12

Digital Inputs

• User Button = P1.16
• Reset Button = P0.18
• Hall-Effect Switch = P0.15

Programming and Debugging

Applications for the croxel_cx1825/nrf52840 board configuration can be built and flashed in the usual way (see :ref:`build_an_application` and :ref:`application_run` for more details).

Flashing

Flashing Zephyr onto the croxel_cx1825_nrf52840 board requires an external programmer. The programmer is attached to the SWD header.

Build the Zephyr kernel and the :zephyr:code-sample:`blinky` sample application.

.. zephyr-app-commands::
   :zephyr-app: samples/basic/blinky
   :board: croxel_cx1825/nrf52840
   :goals: build
   :compact:

Flash the image.

.. zephyr-app-commands::
   :zephyr-app: samples/basic/blinky
   :board: croxel_cx1825/nrf52840
   :goals: flash
   :compact:

You should see the red LED blink.

References

[1]	https://croxel.com/ble

[2]	https://croxeldata.s3.amazonaws.com/cx1825/CX1825-01_SCH_200424A.PDF