How to get Bluetooth Bootloader up and running??

[Flemming Jensen]

Hi,

I am having BIG problems getting the Bluetooth Dual Bank Bootloader sample to work!

I am using Keil 5.18 and using SDK version 9.0.0 and also tried 10.0.0. I have S310 working together with a application using both ANT+ and BT. No problems what soever...

But now I want to add a bootloader functionality so that I can update the firmware remotely if I need to.

I use the following recipee:

• First I clear the CPU using nRFStudio
• Then I install Softdevice S310 v3.0.0 in the device (116KB)
• I use the sample BLE_DFU_DUALBANK_S310 (not sure this is the exact name :))
• From either V9 or V10 SDK
• Build the project (which takes 3 compile iterations optimizing for size)
• I have then tried installing the bootloader 2 ways.
• One way is just clicking upload in Keil which uses jrfprog
• Second way is using nRFStudio and install the bootloader here by using the .hex file

I reset the board and then use "NRF Toolbox" on my Android Phone to try and search for the device. But it never comes up.

Actually I think it crashes becuase I cant even lit a LED....

I am pretty stuck here. I cant seem to be able to single step the bootloader for some reason. This way I could possible identify what is going wrong...

Please help

[Vidar Berg]

From your description it sounds like you're doing everything correctly. Please add a screenshot of the register view in Keil when you're debugging to see whether the program execution may be stuck in the hardfault handler.

[Flemming Jensen]

Hi Vidar,

I think I end up in a hardfault or something. (The PC is near the start of the flash - So its inside the S310)

I have been speculationg about something... How does the CPU findout where to start executing code? Because now with the bootloader it needs to start at 0x3c000? Right?

Flags? Jump table?

Your inputs are much appriciated!!!

[Vidar Berg]

It is the MBR that forwards execution to the bootloader on startup when present (checks the UICR.BOOTLOADERADDR register) => Master Boot Record (MBR) and SoftDevice reset behavior.

Yes, 0x3C000 is the default start address for the bootloader. You can verify that it's set by reading the register through the memory window in Keil, or use nrfjprog:

nrfjprog --memrd 0x10001014

MBR will forward execution to SD if it's not set.

[Flemming Jensen]

Hi again Vidar... This is very interesting input... I will investigate later this evening. Maybe I should start by trying the single bank DFU to get started. BTW. how can the bootloader update the softdevice using DualBank? Doesn't it need double space as the softdevice ? fx 112KB? Thank you very much for your input.:)

[Vidar Berg]

Only dual bank example is provided for OTA DFU. Although to make it single bank you only need to replace dfu_dual_bank.c with dfu_single_bank.c in your project. Softdevice requires the application to be erased because of space limitation as you mentioned. Purpose of dual bank is to allow the bootlaoder to enter the old application in case application dfu fails. With single bank it has to fall back into DFU mode as the old application is erased.