Simple Method to call bootloader from Applicaton

RE: Simple Method to call bootloader from Applicaton

TimW — Sat, 23 Mar 2019 17:06:39 GMT

This just in... I have it working now.

I'm not sure which of these things fixed it but my application doesn't use buttons.

1) I did not have NRF_BL_DFU_METHOD_GPREGRET enabled in my SDK. I'm not sure when in the firmware that actually applies but somehow I missed it before.

2) I compiled my application with a different soft device than the DFU bootloader.

I can now program my app from my own version of the DFU bootloader and then switch back from my app to the DFU bootloader on command!

-Thanks and I will open a new question if I have more.

RE: Simple Method to call bootloader from Applicaton

TimW — Fri, 22 Mar 2019 20:09:16 GMT

Also, I have successfully created the ButtonLess application and loaded it from the secure bootloader using the bluetooth nrfutil.

Question: What action do I take with the bluetooth app to reboot the bootloader?

The info suggests that I write a 01 to a characteristic.. which characteristic?

Here is my screen:

RE: Simple Method to call bootloader from Applicaton

TimW — Fri, 22 Mar 2019 19:48:07 GMT

Yes I am using the secure bootloader to load my Application successfully. (I have generated my own keys as well). My problem is, when triggered, my application does not re-enter the bootloader. Instead it just reboots back to the application.

Here is the simple code I wrote in main that successfully gets called when I want to restart the boot loader.. but the bootloader doesn't start:

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Also.. I halted the App and read the memory:

Here is what is in 0xff8 = 72000 (the bootloader starting address (vectors)

Is this correct?

like wise I know the secure bootloader is still there as shown HERE:

What am I not seeing??

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RE: Simple Method to call bootloader from Applicaton

Hung Bui — Fri, 22 Mar 2019 17:33:00 GMT

Have you tried to test the DFU bootloader ? Please make sure you fully know how to use it before testing with the buttonless.

I have a step by step guide here that you may want to have a look.

RE: Simple Method to call bootloader from Applicaton

TimW — Fri, 22 Mar 2019 16:43:34 GMT

Yes,

When I call ble_dfu_buttonless_bootloader_start_finalize() and reset, my app reboots to itself.

Could it be that I don't have the bootloader address set in 0xFF8 of the MBR?

RE: Simple Method to call bootloader from Applicaton

Hung Bui — Fri, 22 Mar 2019 16:26:55 GMT

Hi Tim,

Have you tried our buttonless application ? It's located at \examples\ble_peripheral\ble_app_buttonless_dfu.

Basically you would need to the retention RAM GPREGRET a magic word (0xB1) and then trigger a reset.
Please have a look at ble_dfu_buttonless_bootloader_start_finalize() function in ble_dfu.c in the buttonless project.

and function dfu_enter_check() in nrf_bootloader.c in the bootloader project. I assume you are using SDK v15.x