Looks interesting 
thanks I’ll give it a try.
please share you’re feedback later 
Will do ! as soon as I have time. Maybe Monday.
Hey,
you might want to try this: https://github.com/arendst/Sonoff-Tasmota,
it provides (after flashing) online access via a webgui and MQTT which works very nicely together with HA.
Plus, this firmware works with all kind of sonoff devices as well as a few others.
SonOTA is using the Tasmota as basis, from what I read it based on the following:
The included final Arduino Sketch binary is v5.8.0 from the Sonoff-Tasmota releases page
Once installed you should be able to upgrade to any other version.
I have ordered a Sonoff S20, so I hope it will work as I don’t have any soldering or serial equipment.
For most Sonoff (and many other units) soldering is not a need. You can get away with a 4 or 5 pin female header some breadboard cables and a USB to UART converter. Most boards have a dedicated 4-5 pin row of vias to connect via serial port. What you basically have to do, sort out the wiring on the PCB and connect the cables between the serial adapater and the female header pin accordingly. Then place the female header into the vias and press it against one side in a way that all the pins get a good contact to the vias. You do not need a lot of force, just a bit pressure to the left or right side and try to not shake. Start the flashing procedure and keep it steady during that 1 min or so… finish… pull off the female header and that’s it.
I have done it this way many times (including S20 units), as I am usually to lazy to solder a pin header to the PCB. If you are satisfied with the firmware, there is no need for that pin header anymore, thus why soldering a header permanently. By the way this is almost the same way like the factory is flashing the firmware (although the most likely use dedicated pogo pins).
Having a good USB to UART converter is always handy. Make sure you get one with adjustable voltage outputs (5V and 3.3V) and good access to the UART pins. An additional power line helps to power the controller during flashing…
NEVER TRY TO FLASH USING THE MAIN POWER OF THE SONOFF UNITS!!! A few mm away from the area you going to touch, you will find 110/230V. Thus always remove the unit from mains and use a dedicated 3.3V power source.
Someone has:
But it’s not trivial to set up.
I’ll trying this out tomorrow (Sunday).
I’ll check it out thanks…
This does work, being the first time I’ve done this process and it took some time. I ended up using a old router that I reset to default and not hooked up to the internet. Also, made sure that windows firewall was disable. The next device will be much easier.
soundss like a good Idea…
I just created a proposal based on that link:
Hi,
so I went for the Tasomta Instalation. Piece of cake. i soldered a 5 pin head to the sonoff, was quite easy. (remember do NOT connect the sonoff to the mains while messing aroud in the sonoff, also you lose warrenty).
All in all this does seem to be the easyist way to do this.
I ran the SonOTA.py on a pi3 connected via Ethernet on my LAN.
I do not understand with which device shall I
“Connect to the ITEAD-* WiFi network, you may need to reset your Sonoff to defaults to do this. This stage tells the Sonoff where to get future updates.”
my android smartphone, while the pi3 is running the SonOTA.py ???
use windows or linux laptop/pc as it requires you to change/connect to the correct WIFI SSID in order to connect to your sonoff device during the setup to complete the installation procedures.
is it possible on a android smartphone?
I dont think so, I just followed the windows instruction to the letter.
You have a Pow right?
You had to calibrate it for correct KWh and W reading?
no, I have S20, no issues with the SonOTA setup.