Write serial number after flashing works with commander but not API

[edcloudcycle]

Hi,
First, thanks to all the contributors, PyOCD is awesome!

I have got stuck however, I am flashing a Nordic NRF52832_xxAA with a hex file and then I need to write a uint16 serial number to an address in the UICR flash. I have got this working great with commander but for some reason the device does not boot after using the API. I think perhaps I am using the incorrect API tool for the job and too much flash is getting erased when I make the write.

My commander script is:

(.venv) PS C:\WorkingDir\tm-jtag-cmsis-dap> pyocd commander
Connected to NRF52832 [Sleeping]: 10930000313855391239333437353533a5a5a5a597969906
pyocd> status
Core 0:  Sleeping
pyocd> erase
pyocd> load TM_v1.7.hex
[==================================================] 100%
pyocd> read16 0x10001080 8 
10001080:  ffff ffff ffff ffff                        |........|
pyocd> write16 0x10001080 7 65535 65535 65535 
pyocd> read16 0x10001080 8
10001080:  0007 ffff ffff ffff                        |........|
pyocd> reset
Resetting target
pyocd> status
Core 0:  Sleeping

My API script is:

with ConnectHelper.session_with_chosen_probe() as session:

    board = session.board
    target = board.target
    flash = target.memory_map.get_boot_memory()

    # Load firmware into device.
    FileProgrammer(session).program("TM_v1.7.hex")
    
    loader = FlashLoader(session, chip_erase='sector', smart_flash=True)
    loader.add_data(address=0x10001080, data=[0x08, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff])
    loader.commit()

    # Reset, run.
    target.reset_and_halt()
    target.resume()

Should I be using something different in the API script to perform the equivalent of a write16?

Thanks very much

Ed

[edcloudcycle]

Ok I think I managed to figure this out but it would be good to get any suggestions to make it better. It was not very intuitive that I would need to call an init() function and that I would need to set the region explicitly when I am already passing the target. Perhaps I have missed an example somewhere!

    board = session.board
    target = board.target
    flash = target.memory_map.get_boot_memory()
    
    # Load firmware into device.
    FileProgrammer(session).program("TM_v1.7.hex")

    flasher = Flash(target, flash.algo)
    flasher.region = flash
    flasher.init(operation=Flash.Operation.PROGRAM)
    flasher.program_phrase(address=0x10001080, bytes=[0x07, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff])

    # Reset, run.
    target.reset_and_halt()
    target.resume()