Comments: SparkFun Pro nRF52840 Mini Hookup Guide


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  • Member #1081731 / about 3 years ago / 1

    I was wondering if the board supports non-Arduino development tools. If yes, what are those?

  • Member #81900 / about 4 years ago / 1

    Heads up, as of this post the analog input (AINx) is swapped in the pin out image. It should be: P0.2 | AIN0 and P0.3 | AIN1

    I've sent feedback. Hope that saves someone time!

    • santaimpersonator / about 4 years ago / 2

      Update: We just corrected the graphical datasheet and board definition files. Thanks for the feedback.

  • kevinvw / about 4 years ago / 1

    Hi, the nRF52840 supports I2S, but the specs for your board do not mention I2S. Are there any issues using I2S? I would like to connect a 24bit PCM1808 Audio Stereo ADC to the SparkFun Pro nRF52840 Mini board using I2S. Specifically I am thinking of using this baord:

    Do you see any issues doing this? Thanks, Kevin.

  • Member #993439 / about 4 years ago / 1

    Hi, I am encountering a situation where my sketch for the nrf52840 sparkfun board only works while in DFU mode. After uploading my firmware if I reset, the blue led flashes briefly and fades out quickly, the board appears to turn off. The Arduino serial console shows nothing. But if i enter DFU mode and restart the console then the board starts and my firmware and BLE works.

    This board does not appear to work in anything other than DFU mode. Powering it by battery doesnt work at all. Kind of a bummer.

    I will probably try powering the board externally with a 3.3V regulator. But this really shouldn't be necessary. Clearly there is something wrong with this board or the voltage regulator/usb power chip.

    • santaimpersonator / about 4 years ago / 1

      Hi there, it sounds like you are looking for technical assistance. Please use the link in the banner above, to get started with posting a topic in our forums. Our technical support team will do their best to assist you. Unfortunately, I am not really familiar with the nRF52840 and don't have any troubleshooting tips for you.

  • Member #1517418 / about 4 years ago / 1


    I recently just purchased one of these boards from a local supllier in Australia, and just had a few questions on how to best go about using it for a wearable sensor device university project. I haven't dealt with embedded system programming much before or BLE technology, so I am a bit unsure on a few things.

    Specifically, my questions are as follows:

    1) Is the available Nordic Semiconductor SDK fully usable with this board upon making the changes noted in the software development guide (e.g. revision of make files, inclusion of board-specific header file etc.)?

    2) If I were to then take the device one step further and use the nRF52840 SoC within my own custom circuitry, what sort of programming changes would this likely require? Could I use much of the same code and make some simple refinements?

    3) Can the board be programmed through BT? Or is USB the main option? I noticed that in the adafruit-nrfutil and Python 3 section (Using the Bootloader) it says the updating can be completed over either serial or Bluetooth, and I read in the nRF52840 datasheet that the SoC has Over-The-Air DFU capability (not too sure if this carries over to broaderd system programming...).

    Apologies if any of the above is not quite correct or even silly. Just trying to get a good idea before I delve too far into it.

    THANKS! :)

  • Member #1484988 / about 5 years ago / 1

    Does applying power to Vin recharge the LIPO or is that only available via the the usb?

    • Member #716454 / about 2 years ago / 1

      Vin is reverse protected by a diode, no current will flow into the battery, and you don't want uncontrolled voltage/current running toward your battery anyway. You can connect your voltage to the Vusb net (CHG led, pad closer to the USB connector, or Pin 4 of the charger IC. This board has no undervoltage lockout for the LIPO to overdrain? Or the LDO will turn off at safe level?

  • Member #1259214 / about 5 years ago / 1

    Regarding: "Using an nRF52840 DK to program the Pro nRF52840 Mini Breakout via the 10-pin Cortex-debug connector." Where can I get the cable shown in the image and utilized to program the nRF5280 via the Nordic nRF DK? Thanks

    • jimblom / about 5 years ago / 1

      Great question! The cables are oddly hard to find... This has worked for me.

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