Is this a new Sonoff device? Sonoff Mini

Yes… either compile your own Tasmota or flash minimal Tasmota first. Then you should be able to flash the full firmware.
Reason is that 2 versions of firmware need to exist in the Sonoff simultaneously and with 1024kb or memory take out the ewelink firmware size and you only have 608k… so tasmota-minimal is less than that and it will then release the memory used by ewelink and then you will be good to load the full firmware.

Can someone who has a Sonoff Mini please confirm if the S1 and S2 pins used for an external switch are connected to full line power or just low voltage that a simple pushbutton could be connected to?

From what I’ve I read in the documentation, S1 and S2 need to be connected to two sides of a rocker switch. It specifically states not to connect live or neutral to these terminals so that would suggest that they are low voltage. The docs also specify that self return rocker switches (push button/momentary) are not supported which to me reads as though it detects each state change, so a simple push button would count as two events each time you pressed it. Again, only what I get from reading the docs and using stock firmware. I’ve not tested the switch function personally.

FYI; I got a e-mail reply from Shelly 1 developers (Allterco) that they are working on a dimmer version of the Shelly that should be on the market within a few months. No information on its capabilities or price.

Personally I already have a few Z-wave dimmers from Fibaro, Aeotec/Aeon-Labs, and Qubino, and so far the Qubino Flush Dimmer is in a higher class of its own and far better than those from its competition. The others do not have the same response-time (switch-press to lights-on or lights-off) or smooth-dimming as Qubino Flush Dimmer, and I have also found that Qubino Flush Dimmer is compatible with many more type of dimmable LED-lightbulbs/lights, dimmable LED-drivers and dimmable halogen-transformers without flickering, which is surprisingly common with LED lights even LED-lightbulb manufacturers claim to be “dimmable”, and so far I had best result with Philip LED lights and OSRAM LED-drivers/transformers

I will be buying a Shelly dimmer when they come out to try it, but if it performs as poorly as Fibaro dimmers or Aeotec/Aeon-Labs dimmers then I will stick with Qubino Flush Dimmers even if they cost a lot more.


You name: stock firmware. With esphome you can do what ever you want on the input. Technically the switch input is properly just a ground pin and a gpio pin from the esp - nothing less - nothing more :exploding_head:

You can just use it as a switch input but tune it with esphome config to detect double presses or a special series and do special things :thought_balloon:

  • What could be a triple switching in less than two seconds? Maybe a turn all lights on :bulb:
  • What could be the super secret sequence you need to follow to open the secret door? :door:
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I managed to solder some wires to the solder pads and flash it with tasmota, it is the same procedure as the sonoff basic.

I use the Sonoff Basic module

I got the physical switch (S1&S2) working with GPIO4 set to Switch1


Anyone tried to flash it OTA maybe?

I have successfully flashed via OTA using the Sonoff DIY Tool after adding Sonoff to eWeLink and updating to lastest firmware 3.3.0 before adding the jumper and going into DIY mode.

I was able to flash the smaller tasmota-classic via the Sonoff DIY Tool and the use WPS to get it on my WiFi. After that I was able to use the Tasmota interface to upgrade to full Tasmota firmware.

I also tried to solder wires to the contact pads and ended up breaking off two contact pads.

My favorite option for getting custom firmware on the Mini is using my custom 3D printed programming jig and pogo pins. I have published the 3D print files on thingiverse for anyone else who would like to try it. This method allows you to directly flash new firmware without ever connecting the Sonoff Mini to Sonoff servers in China and will allow you to flash firmware up to 1 MB in size instead of the 508KB OTA limit.!


Have a look at DrzzzS YouTube he just posted a video on how he flashed OTA.

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So i’ve managed to solder some wires just like you but i can’t flash my Mini. The flasher doesnt connect to it. You just soldered the wires and connected to the FTDI? Nothing else?

Yes, i only soldered the wires to it, and connected those to the FTDIlike shown in the pictures.

You have to press the B button while powering up to get the board in programming mode. Did you do that?

After update the firmaware with tasmota the 3-function still working? Thanks

That is a very nice jig!

Haven’t read it all, but this seems to be the same thing?

Thats a zigbee one. I have 2 of those and they work really well with Conbee/Phoscon

Hi All,

i have one Sonoff Mini Switch flashed without problems with ESPHome and using the pads and FTDI device. The only trick that is needed when powering up, is to press the button to enter in boot mode.

But now, I’m trying to set it up using ESPHome and I’m struggling to get the GPIO numbers of the relays and external switch.

Anyone has figure out what are the GPIO numbers for the different components in the board?
Status LED, Relay and external switch?

Many thanks!


Hi All,

i will reply myself.

The pinout of the Sonoff Mini is the following:
GPIO0 = Button
GPIO4 = External Switch
GPIO12 = Relay


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I can confirm that it doesn’t need cloud setup in DIY mode.