How to upgrade firmware using dfu first time?

[abhinav]

HI, I am using sdk 8 and pca10028 dk. I follow following procedure,

• Program the softdevice using nrfgo
• Program the test_bootloader using nrfgo
• Program the application using keil. My problem is that on startup it goes into bootloader mode and start advertising as dfuTest but I want it should go into application and start working with it. Please provide solution on how I should achieve it. Regards , Abhinav.

[Øyvind Karlsen]

Hi,

This is covered by the tutorial on setting up DFU. Please let me know if you have any questions or troubles following this tutorial.

Best regards,

Øyvind

[Øyvind Karlsen]

As described in section C. of the common FAQ on DFU:

Buttonless DFU means we start the DFU mode from the application without the need of a physical button. The main technique is to set a flag, could be the retention register GPREGRET, or write to flash, etc. And then jump to bootloader either by a reset or directly branching.

Note that the bootloader is always executed before the application. If there is a valid application and if there is no request for DFU, it will forward interrupt and start the main application. This is the reason why we need to set a retention flag to tell the bootloader to enter DFU mode instead of starting the application.

This means that you have either not got a valid application, or you have set the GPREGRET flag.