Flashing Micropython 1.21 to an ESP-01m not possible

[besi]

I was not able to flash my ESP-01m with the latest micropython version 1.21.
As soon as I did a fallback onto 1.20 I could successfully flash my device and get a REPL.

EXPECTED BEHAVIOUR

I flash the device and get a REPL when connecting to it via TTL cable.

ACTUAL BEHAVIOUR

I can flash the device and "Thonny" tells me that the flashing was complete. However when I disable the boot loader mode and reset the device the device fails to respond.

I did use the latest Thonny 4.1.4 which uses ESPTool in the background.

I quite like the form factor of the ESP-01m so I would hope that micropython continues to work on that device.

[robert-hh]

Try to flash the firmware with other flash modes, like DOUT.

[besi]

That did the trick along with flash size detect. Thanks very much

[besi]

That did the trick along with flash size detect. Thanks very much

[besi]

I still find it problematic that Esptool let’s me flash the device all the way only then to let me realise that I need to change some of the settings. I wonder if that is due to hardware limitations or if it could be fixed in software.

[Josverl]

Perhaps you can add to the issue reported on the esptool repo : espressif/esptool#816
I see that you started this, but that would be the best place to get the answers you are looking for.