Lolin C3 problems

[Electroguard]

A quick heads-up... I have 2 different models of Lolin C3 devices, both which exhibit the same problem after reporting a succesful green button flash of Annex using the USB option, but both having 0 bytes of Flash free available after, therefore both being unusable because of not being able to Save files.

https://www.aliexpress.com/item/1005004 ... PMTw2kYHmy

https://www.aliexpress.com/item/1005004 ... ec%21FR%21

[cicciocb]

Hi Robin,
try this version

[Electroguard]

The symptoms have changed Francesco, the modules appear to flash ok as before, but now they cannot be connected to in the browser, and linux keeps reconnecting the wifi ... so I think they may be repeatedly rebooting themselves.

[cicciocb]

So try this other version

[Electroguard]

Yay !
Well done sir... now has Flash free available and is able to save script from Editor.
Only quickly tried with one device so far cos about to go out, but no reason to think it will not work with the other devices. so will give a more thorough test this evening.

[Electroguard]

Was only a partial success, that earlier first one seems to work ok, but the other two C3 devices still have problems, although with a different symptom to before... both still report Flash success, but neither shows up in wifi SSID, so unable to connect.

The strange thing is that one of these similar devices does work now, yet the other one still does not, despite both looking physically identical (although they were bought at different times from different sellers)... https://www.aliexpress.com/item/1005004 ... PMTw2kYHmy

This other device is physically very different, but reports exactly the same blue button info (see screendumps below), and (as I discovered by accident) unlike the first two it does allow flashing automatically (not holding button with USB selected)... https://www.aliexpress.com/item/1005004 ... ec%21FR%21

All three do not recognise the CPU Speed.

c3ok.jpg

c3b.jpg

c3c.jpg

[cicciocb]

Have you tried to flash these modules with the first bin I sent?
Edit

In fact these chips (esp32-s2, esp32-c3 and even esp32-s3) seems to have a different arrangement (DIO / QIO) with the memory that cannot be overridden during the flash phase but must be integrated in the compile phase.
Basically the bins I posted are exactly the same source code but compiled slightly differently.

[Electroguard]

Yes. tried the first update on all C3 devices without success.
Then tried the second (last) update with only partial success on one of the smaller type as reported yesterday.
Didn't touch that one that now works, but retried flashing the two faulty devices with both of the updates again just to be sure - they still both report flash success, but neither shows up in the list of wifi SSIDs after, so am unable to connect.

But one interesting fact I discovered is that although all three C3 devices report identical blue button info, the single larger module returns blue button info without needing to select 'USB' and hold the USR button in... and it also does a green button flash without using the button and Usb.

So I physically deleted the Annex32C3usb.bin file from the build folder, then did a non-Usb C3 flash which again reported success, again without any wifi SSID available after. So I'm guessing that the same problem exists in both the C3 and C3Usb bins.
So if there is a 1.49.22 Annex32C3.bin available (not the Usb version) I could give that a try on the larger type of device.

[cicciocb]

Your modules do not have the USB to Serial chip onboard so will not work with the - non USB - version

[Electroguard]

That's what I was telling you Francesco, this C3 device DOES have onboard serial... https://www.wemos.cc/en/latest/c3/c3_mi ... 2a59PyERCA
It even has pins labelled TX and RX.
It must be built in to the ESP chip, because I cannot find a separate serial UART chip.
It very definitely responds to Toolkit without holding a button in USB mode.
The blue button auto-responds with chip info and jumps to the Toolkit C3 tab.
Doing a green button in C3 tab without USB selected does an auto-flash using Annex32C3.bin
It flashes 100%, then pops up a window saying the flash was successful.
But after a reboot the device does not broadcast an SSID, which is exactly the same symptoms as the other C3 model that definitely dows not have onboard serial, and does require holding the button while in USB mode.

This device is pin compatible with wemos D1 Mini footprint (including TX, RX) plus has bluetooth, and costs less than most... so would be a good asset if it was usable with Annex32.

https://www.aliexpress.com/item/1005004 ... ec%21FR%21

c3serial.jpg