buttonless app jlink dfu

[Stas]

I try create my own app based on buttonless app. I've tested dfu over the air it's ok. But for that I need to firmware bootloader (with security key) before. It's ok for production, but while I work on my app I need to firmware chip very many times and of course do it through jlink debugger much more convenient. With previous SDK versions I could do it, I just didn't load the bootloader into chip and it's ok, now I got error in log "no bootloader", if I load BL I can't load my app via Jlink. What's the best way of doing my thing?

[Hung Bui]

Hi Stas,

As I understand you want to flash softdevice, bootloader and application using Jlink. To do that you need to tell the bootloader that you have a valid application. A bootloader setting modification needed. Please have a look at the Appendix A in this guide.

[Stas]

sorry for long delay. After I commented part of code where we check crc ( if (crc != s_dfu_settings.bank_0.image_crc)), I can program app via Jlink. But I loose ability to do it wirelessly via smartphone. Now after flash bootloader I can see only led 2 on my nrf52dk and can't see now DfuTarg while scanning in nrfconnect. Is it ok? After I uncommented crc checking part of code, I can see both leds and DfuTarg advertises me.

About change crc to 0. if I understood correct we need to change that in settings file generate based on our_app.hex file so in my case it's 0x82461E8A. I've found it in settings.hex. How I have to change it to 0? I tried just replase 82461E8A to 00000000. After that I was not able to merge it with bootoader.hex