How to add buttonless_dfu and serial_dfu functions at the same time.

[June6]

Now the code in the application part has added the buttonless_dfu function, which has also been successfully implemented. But I ’m not familiar with serial_dfu, I don’t know how to continue to add serial_dfu function. And how to achieve coexistence of ble_dfu and serial_dfu in bootload code？

[Hung Bui]

Hi June, 

You can have a look at this case: https://devzone.nordicsemi.com/f/nordic-q-a/35431/dfu-over-ble-and-usb

I have an example for SDK v15.2 there. To find how to enter DFU bootloader mode from application, please study the ble_app_buttonless_dfu example. Check function enter_bootloader() and then ble_dfu_buttonless_bootloader_start_prepare(). The GPREGRET register is written before the application reset and enter bootloader. 

[June6]

Hi Hung Bui，

I have added the serial_dfu code with reference to this routine, and now I have a few questions:

1、Does uart need flow control during serial dfu? I am currently turning off serial port flow control because my hardware does not have two pins for flow control

2、In normal application operation, in addition to the buttonless method, I can also enter the upgrade mode by pressing the button. After pressing the button, I performed the following operations:

err_code = sd_power_gpregret_clr(0, 0xffffffff);
VERIFY_SUCCESS(err_code);

err_code = sd_power_gpregret_set(0, BOOTLOADER_DFU_START);
VERIFY_SUCCESS(err_code);

// Signal that DFU mode is to be enter to the power management module
nrf_pwr_mgmt_shutdown(NRF_PWR_MGMT_SHUTDOWN_GOTO_DFU);

Is this correct?

3、After entering the upgrade mode, what nrfutil command is used to upgrade the zip package into the chip?

[Hung Bui]

Hi June, 

1. You may need to reduce the baudrate down to 9600kbps. Have a look here: https://devzone.nordicsemi.com/f/nordic-q-a/59095/serial-dfu-with-higher-baudrate-using-custom-nrf52832-board-and-sdk-15-2

2. I think that's fine. 
3. Please follow the documentation: https://infocenter.nordicsemi.com/topic/sdk_nrf5_v16.0.0/sdk_app_serial_dfu_bootloader.html?cp=7_1_4_4_4

[June6]

Hi Hung Bui,

When the hardware enters dfu mode and executes the 

nrfutil dfu serial -pkg production_DFU.zip -p COM13

  command, serial_dfu still does not work.

The following is the error result returned

Traceback (most recent call last):
  File "D:\Application\Python38\Scripts\nrfutil-script.py", line 11, in <module>
    load_entry_point('nrfutil==6.0.1', 'console_scripts', 'nrfutil')()
  File "D:\Application\Python38\lib\site-packages\click-7.1.1-py3.8.egg\click\core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "D:\Application\Python38\lib\site-packages\click-7.1.1-py3.8.egg\click\core.py", line 782, in main
    rv = self.invoke(ctx)
  File "D:\Application\Python38\lib\site-packages\click-7.1.1-py3.8.egg\click\core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "D:\Application\Python38\lib\site-packages\click-7.1.1-py3.8.egg\click\core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "D:\Application\Python38\lib\site-packages\click-7.1.1-py3.8.egg\click\core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "D:\Application\Python38\lib\site-packages\click-7.1.1-py3.8.egg\click\core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\__main__.py", line 1055, in serial
    do_serial(package, port, connect_delay, flow_control, packet_receipt_notification, baud_rate, serial_number, True,
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\__main__.py", line 970, in do_serial
    dfu.dfu_send_images()
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\dfu\dfu.py", line 127, in dfu_send_images
    self._dfu_send_image(self.manifest.application)
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\dfu\dfu.py", line 88, in _dfu_send_image
    self.dfu_transport.open()
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\dfu\dfu_transport_serial.py", line 217, in open
    self.__get_mtu()
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\dfu\dfu_transport_serial.py", line 364, in __get_mtu
    response = self.__get_response(DfuTransportSerial.OP_CODE['GetSerialMTU'])
  File "D:\Application\Python38\lib\site-packages\nrfutil-6.0.1-py3.8.egg\nordicsemi\dfu\dfu_transport_serial.py", line 504, in __get_response
    raise NordicSemiException('Response Code {}'.format(
pc_ble_driver_py.exceptions.NordicSemiException: Response Code NotSupported

[June6]

1. I have ensured that the pc-nrfutil-master version is the latest (6.0.1)
2. The serial port baud rate has been changed to 9600, HWFC false
3. I also tried to change dfu_transport_serial.py in pc-nrfutil-master \ nordicsemi \ dfu. The changes made are as follows

DEFAULT_BAUD_RATE = 9600
DEFAULT_FLOW_CONTROL = False

And executed 

python setup.py build

and reinstalled 

python setup.py install