Python DFU util

[iabdalkader]

Yes it doesn't matter where it lives, as long as it's somewhere in the same repo.

[blmorris]

Hey guys - nice work, and I'm excited to use this, but I can't get it to work on my Mac.

Running python3.4, I installed pyusb using "sudo pip3 install --pre pyusb"
This worked, eliminated the first error message I got:

Code: Select all

Traceback (most recent call last):
  File "pydfu.py", line 20, in <module>
    import usb.core
ImportError: No module named 'usb'

However now I get the following:

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stmhal bryan$ python3 pydfu.py -u build-PYBV10/firmware.dfu 
File: build-PYBV10/firmware.dfu
    b'DfuSe' v1, image size: 247553, targets: 1
Traceback (most recent call last):
  File "pydfu.py", line 527, in <module>
    main()
  File "pydfu.py", line 514, in main
    elements = read_dfu_file(args.path)
  File "pydfu.py", line 295, in read_dfu_file
    img_prefix['name'] = cstring(img_prefix['name'])
  File "pydfu.py", line 242, in cstring
    return string.split('\0', 1)[0]
TypeError: Type str doesn't support the buffer API

Any thoughts? I haven't tried to dig into the error message yet, just wondering if there is something obvious, maybe another library package, that I might be missing.
-Bryan

[iabdalkader]

Line 242:

Code: Select all

    return string.decode('utf-8').split('\0', 1)[0]

Also fixed it in my repo and confirmed working with Py3

[blmorris]

@iabdalkader - That did it, and just as intended it jumped to application mode without me needing to remove the DFU jumper and press reset. Thanks, and nice work!
-Bryan

[dhylands]

@blmorris: There is a pyb.bootloader() command so that you don't even need the DFU jumper any more (except in rare cases).

[iabdalkader]

@blmorris: There is a pyb.bootloader() command so that you don't even need the DFU jumper any more (except in rare cases).

I saw the tear-down approach and jump to DFU, we set a magic byte instead in SRAM and reset and branch on to dfu, much easier.

[blmorris]

@blmorris: There is a pyb.bootloader() command so that you don't even need the DFU jumper any more (except in rare cases).

True, but if you issue that command from a REPL over USB then it has the downside of clobbering the terminal program by eliminating the tty device it is connected to. Not a catastrophe usually, and it is certainly possible to type 'pyb.delay(10000); pyb.bootloader()' to give myself time to exit gracefully, but I have still found the jumper method to be convenient enough for my purposes
Not to dismiss the utility, of course. I am sure that I will make heavy use of these features to jump back and forth between DFU and application mode once we start putting micropython into our products. For now I was just commenting that the automatic jump to application mode was a nice feature.
-Bryan

[iabdalkader]

True, but if you issue that command from a REPL over USB then it has the downside of clobbering the terminal program by eliminating the tty device it is connected to. Not a catastrophe usually, and it is certainly possible to type 'pyb.delay(10000); pyb.bootloader()' to give myself time to exit gracefully, but I have still found the jumper method to be convenient enough for my purposes
Not to dismiss the utility, of course. I am sure that I will make heavy use of these features to jump back and forth between DFU and application mode once we start putting micropython into our products. For now I was just commenting that the automatic jump to application mode was a nice feature.
-Bryan

It's possible to add a vendor request to jump into DFU, which can be sent from the script, so the whole process (dfu->program->reset) can be done with a single command without ever touching the board.