About BLE communication after DFU execution of nRF 52840

[katokatsu6412]

Hello.
We evaluate DFU using nRF 52840.
After writing sd_s140_bootloader_buttonless_with_setting_page_dfu_secure_ble_debug_without_bonds.hex to nRF 52840-DK, we updated using softdevice_s140.zip using nRFConnect for Desktop. I confirmed that updating was successful, software reset was executed and "Noedic Buttonless" was displayed, but BLE communication with nRF 52 - DK with ble_app _ uart _ c written can not be done.
What kind of setting is necessary?

[katokatsu6412]

thank you for your answer.

The procedure I did is as follows.

1. Create an encryption key with urfutil.
2. Build ble_app_button_dfu and secure_bootloader with armgcc, merge the boot loader setting, boot loader, soft device (S140), application hex file and flush to nRF 52840-DK. (Use the encryption key created in 1)
3. Update using the application (ble_app_uart) zip file using nRFConnect for Desktop.
4. LED 1 of nRF 52840-DK does not blink after completion of DFU.
5. When building with Keil, LED 1 of nRF 52840-DK flashes after DFU finishes.

It seems that the operation differs between armgcc and Keil.
Please tell me how to make it the same as keil with armgcc.

that's all, thank you very much.

[Hung Bui]

Hi, 

Have you checked the application when you built with armgcc (ble_app_uart) works if you flash it directly to the board ? 

If it works, you may need to test first by updating it with the bootloader (no buttonless ) , similar to what in this guide. 

You need to check and see if the application has been copied correctly and if the bootloader jump to the application or not. You can debug the application as it was written normally. 

The protocol to send buttonless to DFU mode is to write 0x01 to the DFU control point , and you need to enable indication before that.