Flash problem

[kjm]

The gpy we're developing some code started to behave erratically, mostly locking up when we tried to run the program from Atom. So we did a full flash erase from the windows cmd prompt

C:\Program Files (x86)\Pycom\Pycom Firmware Update>pycom-fwtool-cli.exe -p COM3 erase_all
Running in FTDI mode
Erasing the board can take up to 40 seconds.
Board erased successfully in 14.1 seconds

then reloaded the firmware with the Pycom firmware updater. But we seem to have gone from the frying pan to the fire, because now we can't download our code

Reading file status
 Failed to read project status, uploading all files
[1/1] Writing file boot.py (50kb)
import ubinascii
 � Failed to write file, trying again...
import ubinascii
>>> f = open('boot.py', 'wb')
>>> f.write( 
NameError: name 'f' isn't defined� Failed to write file, trying again...
import ubinascii
>>> f = open('boot.py', 'wb')
 f.write(ubinascii.a2b_base64('IyAyMTA5c21zRnJvc3Rzb2wucHkgc2VuZHMgYWxhcm1zIGFzIGxvbmcgYXMgdGVtcGVyYXR1cmUga2VlcHMgZmFsbGluZw0KIyBfc2V0UlRDICYgc2VuZCBzcyB0byB1c3JzIG9uIHB3cnVwIG9yIHdkdA0KIyAxNSBtaW4gd2FrZXVwIGNoZWNrIGZv�ets Jun  8 2016 00:22:57

We've not encountered this behaviour before, anybody know what to try next?

[Gijs]

@kjm Does this happen consistently?
It looks like something went wrong when referencing the global f (where the NameError comes from). I was not able to reference the second part of the errormessage Failed to write file, trying again... in the firmware, is that part of the Pymakr output perhaps? It seems like you're able to access the REPL while Pymakr is not done yet..

Could you try os.listdir() to see the files in the current directory, perhaps that could give an indication.

Let me know!

[Elizar]

Did You format the filesystem after flashing the system? Maybe the filesystem is in an inconsistent state that causes write operations to fail.

Try uos.mkfs("/flash") on the command line. [Attention! You will loose all previous data on /flash]. Then upload Your files again.

[kjm]

@Gijs The listdir looks normal to me ['boot.py', 'cert', 'lib', 'main.py', 'sys']
After we tried os.fsformat('/flash') the listdir output changed to ['boot.py', 'cert', 'lib', 'main.py', 'project.pymakr', 'sys']

[kjm]

@Elizar Since we're running LittleFS we tried import os; os.fsformat('/flash')

Reading file status
Failed to read project status, uploading all files
Creating dir lib
[1/1] Writing file lib/onewire.py (8kb)
� 
NameError: name 'f' isn't defin Failed to write file, trying again...
import ubinascii
>>> f = open('lib/onewire.py', 'wb')
 
NameError: name 'f' isn't defined
� Failed to write file, trying again...
import ubinascii
>>> f = open('lib/onewire.py', 'wb')
� 
NameError: name 'f' isn't defined
>>� Failed to write file: 
 f = open('project.pymakr', 'wb')
 
PYB: soft reboot
Pycom MicroPython 1.20.1.r1 [15b6d69] on 2019-11-02; GPy with ESP32
Type "help()" for more information.
>>>  
PYB: soft reboot
Pycom MicroPython 1.20.1.r1 [15b6d69] on 2019-11-02; GPy with ESP32
Type "help()" for more information.
>>>  with open('project.pymakr', 'rb') as f:
...       while True:
...             c = f.read(512)
...                 if not c:
...                            break
...                             hash.update(c)
...                             sys.stdout.write(ubinascii.hexlify(hash.digest()))
...                             
...                             
...  
PYB: soft reboot
Pycom MicroPython 1.20.1.r1 [15b6d69] on 2019-11-02; GPy with ESP32
Type "help()" for more information.
>>> Upload failed: Filecheck failed. Please reboot your device manually.
import machine
>>> machine.reset()
ets Jun  8 2016 00:22:57

Getting the feeling this particular gpy isn't coming back.

[robert-hh]

@kjm You could try the sledgehammer approach and do a full flash erase with esptool.py. That will also remove any flasg and setting that Pycom firmware stores to the flash and will not be overwritten by the Pycom updater. After that, you have to restore the firmware using the pycom online firmware updater, resulting in a device with full factory reset.-
If then the boards fails, the board has probably a hardware defect.

[kjm]

@robert-hh Replaced the usb cable & all good now Rob. Why this particular gpy won't work with the replaced cable when all the others do is a bit of a mystery, the current looks the same, the voltage trace on the CRO looks the same, must be some subtlety there I can't measure that prevented it from running/uploading from the repl.