bootloader issue during flashing

[ostelmakh]

I followed the steps below:
flash softdevice

nrfjprog -f nrf52 --program s132_nrf52_7.0.1_softdevice.hex --chiperase

 
flash bootloader

nrfjprog -f nrf52 --program bootloader.hex

generate package

nrfutil pkg generate --application blinky_pca10059_mbr.hex --application-version 2 --hw-version 52 --sd-req 0xCB --key-file private-key.pem app_test.zip

flash package

nrfutil dfu serial -pkg pp_test2.zip -p /dev/ttyACMO 

But after that I can't connect to this board by using usb and need again connect j-link to flash bootloader.
How can I flash application and then connect to board without j-link?

[Amanda Hsieh]

Hi, 

Vidar made an example that supports serial DFU over UART from the application here. 

-Amanda H.