Boot Mode not working, Latest Firmware not working

[ekwus]

Re: Firmware update (downgrade) failing

I have been trying to resolve a crashing issue with LoPy firmware 1.6.12.b1 and trying to revert back to the previous firmware using this method.

However nothing works, pulling P12 to 3.3V during boot seems to have no effect - the LED flashes slow 3 seconds, faster 3 seconds, even fast 2 seconds, but regardless of when I remove the jumper it alows reports the same firmware version and crashes after a few seconds of operation.

The firmware that came with the board had no crashing issues and I stupidly upgrading the second working board I had to rule out dead hardware.

• Does anyone know if the boot modes work?
• Does anyone have a recently purchased board that works with the latest firmware?
• Is there away to downgrade firmware?

Really starting to think these boards are a waste of money and time.

Cheers

Dave

[robert-hh]

@ekwus You can downgrade to a previous version with the method depicted here: https://forum.pycom.io/topic/517/downgrading-firmware-advanced-users/15
if you want to go to a different version than the ones listed, user a different download URL, like
https://software.pycom.io/downloads/LoPy_868-1.6.9.b1.tar.gz
for version 1.6.9.b1

[jmarcelino]

The safe boot modes should skip the configuration files, but they don't revert the firmware versions - that will work for Over-the-air upgrades (when available) but not for "hard" firmware updates via the update tool.

You can try to downgrade as @robert-hh but I'd try flashing the latest firmware again but deselect the "high speed transfer". I suspect something is getting corrupted in your firmware transfer. Ideally I'd even try another USB-Serial adapter.

[ekwus]

Thanks for the details on boot mode @jmarcelino, PyCom could put a bit more detail in the docs regarding this - the pin out diagram suggests it should work regardless and that it is working now, not a to be added feature.

Regarding the firmware update issue I have resolved it :-) Turns out I was needing a pull-up resistor on the Reset pin - my guess is that noise from the serial pins was enough to cause a reset during the update or maybe I was just lucky the the time I added the resistor.

I was also able to recover my second board with the resistor in place adding weight to the pull-up being required theory.

Thanks for everyone's help.

Cheers

Dave