How To Use nRF52840/nRF52833 module DevKit(MDBT50Q series) – 2024 Update

Hardware Set Up

• 1 x MDBT50Q-DB-XX
• 1 x IDC Wire
• 1 x Data/Power Mini USB Wire

Where to buy MDBT50Q-DB-XX?

MDBT50Q-DB-40 (nRF52840 Solution)

MDBT50Q-DB-33 (nRF52833 Solution)
nRF51, nRF52 or nRF52840 DK Connects with MDBT50Q-DB-40 by IDC wire. Powered up the MDBT50Q-DB-40 by Micro USB wire.

MDBT50Q-DB-40 Schematic

MDBT50Q-DB-33 Schematic

Firmware Set Up Resource
Download nRF Connect For Desktop (Please Click Me)
Download nRF5 Command Line Tools (Please Click Me)
Download nRF5 SDK (Please Click Me)

Firmware Development
1. Download SDK nRF5_SDK_15.2.0_9412b96.zip
2. Unzip SDK
3. Use S140 Softdevice Softdevice (nRF5_SDK_15.2.0_9412b96componentssoftdevices140hex
s140_nrf52_6.1.0_softdevice.hex)

For more detail about the Firmware development, please refer to another article for more detail:

Bluetooth Project: How to get your firmware development started

Firmware Program Steps
1. Selecting Programmer in nRF Connect

2. Selecting Program Device (refer to Nordic DK)

3. Adding Hex File

4. Erase and Write

Note: If MDBT50Q-DB is powered by computer, it may detect USB connection. Pls click “No” to proceed and complete the firmware program.

**MDBT50Q-DB USB DFU
nRF52840 provides USB interface which enable to support Device Firmware Update (DFU) through USB directly.
Hardware Setup
1. Press Switch 4 and Hold
2. Power in the Demo Board
3. Blue LED stays light
4. Demo Board successfully enter USB DFU Mode

Firmware Setup
Note

• USB DFU works in DOS mode only.
• USB DFU only works with previous loaded firmware employs USB Bootloader feature only.
• A single, merged hex file is required. Need to combine Bootloader, Softdevice, and Application.
• Firmware DFU requests a zipped file.

USB Firmware DFU Steps:
1. When MDBT50Q-DB Blue LED Stays Light (shows ready to enter USB DFU Mode)
2. Find out the Com Port No. changed from “nRF52 USB CDC BLE Demo(COMxx)” tonRF52“SDFU USB(COMxx)”

3. Proceed the USB DFU
Enter DOS mode and select the file with the code in below
nrfutil dfu usb_serial -pkg usbd_ble_uart.zip -p COMxx

(usbd_ble-uart.zip refer to the code to update)
(xx refer to Com Port No.)

4. USB DFU Completed

Tips: 

1. Bootloader example Code can be found: 
nRF5_SDK_15.2.0_9412b96examplesdfusecure_bootloaderpca10056_usb
Need to produce “micro_ecc_lib_nrf52.lib” and “public key” for latter development

2. How to merger the firmware 

• Produce: bootloader_settings.hex

nrfutil.exe settings generate –family NRF52840 –application usbd_ble_uart.
hex –application-version 3 –bootloader-version 2 –bl-settings-version 1
bootloader_settings.hex

• Merge bootloader 及bootloader settings file：

mergehex.exe -m Bootloader.hex bootloader_settings.hex  -o output_1.hex

• Merge bootloader 、bootloader settings及softdevice：

mergehex.exe -m output_1.hex s140_nrf52_6.1.0_softdevice.hex  -o
output_2.hex

• Merge the merged bootloader 、bootloader settings、softdevice及application：

mergehex.exe -m output_2.hex application.hex  -o usbd_ble_uart_sd_bt_app.hex

3. Zip the firmware
nrfutil pkg generate –hw-version 52 –sd-req 0xae –application-version
0xFF –application usbd_ble_uart.hex –key-file dfu.pem usbd_ble_uart.zip