Shelly1L Gen3 PIN Layout

[rubenkr]

Hi everyone,

I an trying to understand the pin layout of the new Shelly 1L Gen3. Has anyone accomplished to find the header pins for flashing?

Any ideas and feedback are highly welcome. Thank you 🙏

[sfromis]

Your images keeps the most interesting parts in the dark, both sides of the small vertical add-on board at the top. That's where the fun happens.

[rubenkr]

Ha! Newbie busted!

Thanks I will have a look and post some pictures of it. When I looked at it I didn’t find any labels.

[HofeBY2]

https://templates.blakadder.com/shelly_1L.html

https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.espressif.com/sites/default/files/documentation/0a-esp8266ex_datasheet_en.pdf&ved=2ahUKEwi_k7uW9caQAxWq-QIHHR0aOY04HhAWegQIFxAB&usg=AOvVaw3pqALsZ5amqXhU6ePcTsSA

[sfromis]

Hopefully, the firmware version of the device is still compatible with that older OTA firmware replacement procedure.

[Jason2866]

It is for sure not possible to OTA convert Shelly with newest firmware or new revisions. ALL newer devices needs to be serial flashed

[rubenkr]

Hi all, thanks for your feedback so far. I tried to flash with the mgos-to-tasmota but as described in their GitHub repo it’s not possible after shell firmware I think 1.5 (my device was 1.6 and downgrades are not possible).

leaving me to the option to flash via TTL. But looking at the missing part of the PCB it looks not very promising to me finding the right pins.

is the a pin layout which pins are RX TX GND VCC?

[sfromis]

GND/3.3V should be on the main PCB connectoor, and plausibly TX/RX too, if you trace the pins from the chip. If you have a really steady hand it would "not be impossible" to connect directly to the chip, but that's not a beginner project 😉

https://documentation.espressif.com/esp32-c3_datasheet_en.pdf

[sfromis]

Still, Shelly usually have a decent MQTT interface, good for local home automation. Reasons to replace firmware are not as strong as with many other devices.

And in case it works with Matter, you should already not expect it to be possible to replace ESP32-C3 firmware.

[rubenkr]

GND/3.3V should be on the main PCB connectoor, and plausibly TX/RX too, if you trace the pins from the chip. If you have a really steady hand it would "not be impossible" to connect directly to the chip, but that's not a beginner project 😉 https://documentation.espressif.com/esp32-c3_datasheet_en.pdf

Thank you very much for sharing the layout! I tried to hold dupon pins with 3,3V and GND from my TTL Adapter to Pins 33 and 02 the Shelly blinked with blue led but after that I was not able to “start” it. Maybe i connect to a wrong pin with 3,3V and bricked it.

Still, Shelly usually have a decent MQTT interface, good for local home automation. Reasons to replace firmware are not as strong as with many other devices.

And in case it works with Matter, you should already not expect it to be possible to replace ESP32-C3 firmware.

You sound like those guys over Shelly official forum 😀. Absolutely they have MQTT. But I have all my devices with Tasmota and only the feeling I am forced to use a firmware makes me want Tasmota. Additionally I use the Timer with sunset etc. Shelly is al way different in their config. What you mean with matter not working in Tasmota on ESP-C3 (or not as good)?

I will not give up on trying to solder a connection to those super tiny hair thin pins of the chip. 99% failure rate with my equipment and shaking hand.

I tried tracing the pins on the PCB but was not lucky. If someone was able to find them it is a pleasure if one could share.

[sfromis]

What I mean is that with any device sold with Matter support from the vendor "you should already not expect it to be possible to replace ESP32-C3 firmware". Part of the Matter specification is that certified products has to block firmware access, for security reasons. Just do not expect to be able to replace firmware (flashing Tasmota), unless you replace the chip. I'm not aware of anyone having hacked a way around this.