no safe boot possible

[robert-hh]

@devinv Oh yes. You have to connect P2 to GND and press reset, to go in boot mode.
esptool.py does not support the PIC boot mode setting, it uses the espressif mode switch, which is sadly not supported by Pycom hardware.
And there is a more recent version of esptool.py here: https://github.com/espressif/esptool/tree/4dab24e1b28632d270adf7305fe0d008d1acee99

[devinv]

@robert-hh Thank you so much. I'm back on track.

[devinv]

@robert-hh Is it possible that all what I did could create problem with my sipy sending messages to Sigfox?
It doesn't work anymore.

This was working before

sigfox = Sigfox(mode=Sigfox.SIGFOX, rcz=Sigfox.RCZ1)
s = socket.socket(socket.AF_SIGFOX, socket.SOCK_RAW)
s.setblocking(True)
s.setsockopt(socket.SOL_SIGFOX, socket.SO_RX, False)
s.send(bytes([0x01, 0x02, 0x03]))

But not anymore.
No messages arrives to my sigfox account!?

[robert-hh]

@devinv Erasing flash erase all data, including any credentials that existed. But these will normally be restored when you do a firmware install through the Pycom updater. And that needs to work, because sometimes devices are in a state where only a full erase help.
But you may also ask Pycom service. Maybe Sigfox requires another configuration step.

[devinv]

@robert-hh Sorted. I just had desengage the sequence number on my sigfox account.

[goldfishalpha]

Just for the record, I had a similar issue with a LoPy on a Pysense board.
I foolishly got it stuck in a while loop. Pulling p12 high as per the official documentation could not get me back into REPL to reflash the file system, i.e

import os
os.mkfs('/flash')

Reinstalling the firmware with the 'Erase flash file system' option checked worked the end.

Additional: This is not the first time that the official documentation has been wrong or incomplete.
Maybe an update of docs is in order?

[robert-hh]

@goldfishalpha Pulling P12 high and then pushing the reset button should activate safe boot, which does not execute boot.py and main.py on boot. That's almost the same as typing Ctrl-F at the REPL prompt.

[Martinnn]

@goldfishalpha Are you sure you have P12? As you have noted, documentation is pretty buggy and pinout description a mess. You might well have the wrong pin.

[goldfishalpha]

@robert-hh
To qoute the docs directly, " After reset, if P12 pin is held high (i.e. connect it to the 3V3 output pin), the heartbeat LED will begin flashing orange slowly. If after 3 seconds the pin is still held high..." suggesting that the pin should be pulled high AFTER reset.
In fact I did get a flashing orange led, using this method.
My problem was that it appeared to reset once I released P12. I released P12 because I did not want to go to the prvious OTA firware and only wanted to disable boot.py and main.py.
@Martinn
I am sure that I have P12 (and not GPIO12 or '12') as I get the flashing led..

I haven't solved it yet. Just documenting for posterity.

[ferfersan6]

@goldfishalpha
Did you solve it? Having the same problem on a Lopy 4.0. Thanks!!

[robert-hh]

@goldfishalpha If there is a time window where micropython is running, you could try to push Ctrl-F in a terminal window. That forces a safe boot. Ctrl-C may work too. This time slot is hard to catch, because typically you cannot connect a terminal when the device is in deepsleep. An indication for start would be an increase in power consumption. So if you have a USB dongle which shows that, if gives the trigger.

[goldfishalpha]

@ferfersan6 Good intentions pave the way to hell and I had every intention to reply to this. I know this is WAY too late to reply this but may useful for any experiencing the same issues.
If I remember correctly, I just held the pin high for as long as possible and went through the drudgery of reinstalling the proper firmware. Nothing sophisticated going on here! :)