SDK13.0.04 NRF52832 experimental_bootloader_secure_serial issue

[liyang]

hi, everyone:

I want to use the experimental_bootloader_secure_serial to update firmware with UART,  disable the hardware flow control. 

how to reset system when application, which document can be refered?

[liyang]

my nrf52832 device don't have button, so after enter into application, need  command device into bootloader state, how to implement it?

[Rune Holmgren]

For resetting the device into bootloader mode, use the function "ble_dfu_buttonless_bootloader_start_finalize" in ble_dfu.c. A call to this function is the final step in handling the buttonless operation on the BLE implementation. You should probably copy only this one function over, since the rest of the file is BLE specific.

To run the serial DFU bootloader without hardware flow control, you will need to run it at a very low baud rate. 9600 baud seems to work for us without any issues. This will mean that updates take a bit longer, but if you do not have the extra pins for hardware flow control this is the only solution. 

Best regards,
Rune Holmgren

[liyang]

refer to the website about Experimental: Serial Secure DFU Bootloader:

http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk%2Fdita%2Fsdk%2Fnrf5_sdk.html

but I still don't kown how to generate the hex file, according to our sdk13.0.0.4, we need more document to understand it. maybe a example  otherwise, it will reduce developer speed.

[liyang]

and, run the serial DFU bootloader, the application, How can I upgrade the operation, do I need to close the interrupt or specify the vector table, then reboot to serial DFU bootloader? or other ?

[Rune Holmgren]

The function "ble_dfu_buttonless_bootloader_start_finalize" was named "bootloader_start" back in SDK 13 and works by setting the GPREGRET register, disabling the SoftDevice, setting the vector table used by the SoftDevice when forwarding interrupts to the bootloaders vector table, disabling and clearing interrupts and finally resetting the device.