OpenSK/docs/boards/nrf52840_mdk.md

Nordic nRF52840 MDK

Makerdiary has instructions on their website. They use a custom script to deploy via DFU.

After general setup, you still need these steps:

1. Create the hexfile with the firmware.

   ./deploy.py --board=nrf52840_mdk_dfu --opensk --programmer=none
   

2. Download the script from Makerdiary's GitHub into the OpenSK repository.

3. Run the script:

   py_virtual_env/bin/python3 uf2conv.py -c -f 0xada52840 -o target/opensk.uf2 target/nrf52840_mdk_dfu_merged.hex
   

4. Boot into DFU mode. Keep the user button pressed on your hardware while inserting it into a USB slot. You should see a bit of red blinking, and then a constant green light.

5. Your dongle should appear in your normal file browser like other USB sticks. Copy the file target/opensk.uf2 over.

6. Replug to reboot.

Buttons and LEDs

The big, white button conveys user presence to the application. Some actions like register and login will make the device blink, asking you to confirm the transaction with a button press.

The LED shows the state of the app. There are different patterns:

Pattern	Cause
red glow	busy
red and blue blinking	asking for touch
red, green, white pattern for 5s	wink (just saying Hi!)
constant green	DFU mode