How to enter download mode without access to GPIO-9 ESP32C3 M4N4

[ramier]

Hello everyone,

I'm currently facing a problem with the ESP32C3 M4N4 variant and was hoping someone here could help me with a solution. In the past I've worked with the XXN4 variant of the ESP32C3 and had no problems flashing them without having to manipulate GPIO-9. However, I've recently acquired hundreds of boards with the M4N4 variant and I can't flash any of them.

With my previous setup using the XXN4 modules, accessing download mode and flashing was straightforward without having to pull GPIO-9 to low. Now it seems that the new M4N4 boards won't boot using the same procedure. I don't have access to GPIO-9 on these boards, which seems to be part of the problem.

I'm looking for any advice on alternative methods of entering download mode on the ESP32C3 M4N4 variant, or if there are any changes to the boot configuration that I may not be aware of with this new variant. Any guidance or shared experience with similar issues would be greatly appreciated!

Thanks in advance for your help and suggestions!

[hristesp]

I had the exact same issue - hopefully Espressif reply and take some responsibility for changing how different batches have different requirements for boot mode and strapping pins

[ramier]

So far I have found out that M4N4 is revision 4 of the chip, XXN4 is revision 3 of the chip. https://www.espressif.com/sites/default ... ata_en.pdf

But there is no way to select the chip revision when ordering.