Buttonless DFU jumps to Application not Bootloader

RE: Buttonless DFU jumps to Application not Bootloader

Hung Bui — Tue, 29 Nov 2016 13:14:36 GMT

Could you check what is the value of GPREGRET after you reset to bootloader ? You can print out via UART or RTT.

Could you try to test with our buttonless DFU application that I quoted on my first comment ?

RE: Buttonless DFU jumps to Application not Bootloader

Philipp Mahr — Tue, 29 Nov 2016 12:27:23 GMT

Hi Hung Bui, thanks for the feedback. Yes, you are right CODE_REGION_1_START is application start address. When I manually set the address of the bootloader to 7a000 or the value of the register NRF_UICR->NRFFW[0] nothing happens and I got a freeze. I also tried the NVIC_SystemReset. That one starts with the bootloader but DFU mode is not accessed. In application I already set the GPREGRET register and in bootloader the register is checked.

Forwarding of bonding information is not required.

RE: Buttonless DFU jumps to Application not Bootloader

Hung Bui — Mon, 28 Nov 2016 15:27:36 GMT

Thanks Philipp, it's more clear now. Could you explain why you have these code:

sd_softdevice_vector_table_base_set(CODE_REGION_1_START);   
bootloader_util_app_start(CODE_REGION_1_START);

Note that CODE_REGION_1_START is where your application start, not where the bootloader start (it start from NRF_UICR->NRFFW[0] . In addition, if you want to forward bond information you may need to set them into the no-init RAM memory using svc call dfu_ble_svc_peer_data_set().

I would suggest you to have a look at the function bootloader_start() in dfu_app_handler.c in the ble_app_hrs\pca100040\s132_with_dfu example (our buttonless DFU application example)

One easier way of doing this is to simply set GPREGRET, then disconnect and do a softreset (NVIC_SystemReset). But this way, you don't forward bonding information to the bootloader.

Note that from SDK v12 the bootloader is refactored and is not compatible with the old one, it's strongly suggested to use the new secure bootloader from SDK v12.

RE: Buttonless DFU jumps to Application not Bootloader

Philipp Mahr — Mon, 28 Nov 2016 15:10:00 GMT

@Hung Is this sufficient or do you need more details for specific steps?

Flash devices with batch script in following order: Softdevices, bootloader, app & app valid settings 2) Restart devices (I can see the bootloader is started first due to LED briefly lighting up)
Connecting to device with nRF Connect App
Writting the 'magic word' to our 'DFU service' to trigger buttonless DFU
Devices disconnects correctly
Device restarts into the application (not going over bootloader as LED is not blinking briefly)

RE: Buttonless DFU jumps to Application not Bootloader

Hung Bui — Mon, 28 Nov 2016 14:47:59 GMT

@Philipss: Please state with step by step how you tested your set-up. You can start with step one: flashing the softdevice.

RE: Buttonless DFU jumps to Application not Bootloader

Philipp Mahr — Mon, 28 Nov 2016 14:19:59 GMT

I am suing SDK11 with a makefile project using Eclipse and GCC. Our bootloader is based on Noric examples, though adjusted to our board. In bootloader, we check then content of gpregret to differentiate between button and button-less DFU, e.g. initiating ble stack.

Though, when in bootloader I lightup an LED. Also, during normal startup I see theis LED blinking when going through bootloader. this is not the case, when initiating button-less DFU. Only the application is restarted, which is why I assume something with addresses maybe wrong. I just can find the cause....

RE: Buttonless DFU jumps to Application not Bootloader

Hung Bui — Mon, 28 Nov 2016 12:32:47 GMT

Could you state the SDK version you are using ?

I assume you flashed the normal bootloader before you update the buttonless DFU application via the DFU process, as described here.