Eachen switch

Third party integrations
1

I am wondering if anyone has any experience with this Eachen / ewelink sonoff switch.

Picked it up for $16 (I know there are cheaper sonoffs but they don’t seem to have momentary support last time I looked) and it took about 5 seconds to hook it to my garage door and it works like a champ. But my goal is to get it hooked to HA so that I can have the garage door automatically open based on certain events.

I know most people flash them, I have two concerns there.

  1. The posts I have found have mentioned folks having a lot of trouble with these particular boards due to not all pins being connected to the programming header

  2. The replacement firmware may not support the momentary mode that I need for the door

I tried their IFTT interface and although the account connected it did not seem to do anything at all.

I have a bunch of generic sonoff outlets connected from SmartLife via a HA plugin script, this board seems like it uses a similar pairing process but the SmartLife app doesn’t seem to detect it so I guess the protocol must be different from SmartLife / Tuya.

Any input is appreciated

Thanks

Rob

2

Did you ever figure out how to do this? I’m interested in giving it a try as well.

3

I wound up figuring out the IFTT link and I’ve been using it via that, works phenomenal. $16 and I can tie my garage door into a phone shortcut as well as home assistant. It does not detect whether the door is open or shut but I have a separate sensor to do that.

4

I couldn’t find much info when searching others that had reprogrammed this board, so here are my results:

The board uses a PSF-B85, pinout is here https://www.itead.cc/wiki/PSF-B85 In Arduino IDE it programs as a generic 8285.

The RX and TX pins are not routed on the board, so soldering or steady hands are necessary to program.

GPIO 0: Toggle button (also hold this button during power on to enter programming mode) (active low).
GPIO 13: Toggle LED (active low).
GPIO 12: Relay (active high)

The mode button and LED are not routed to the 8285 AFAICT, however the 4-pin header is (pin 1 = square solder mask):

1: GND
2: Mode Button (active low)
3: Mode LED (active low)
4: 3.3v

So you can use this for power and ground and also there are enough free GPIOs on the 8285 to route a sense line to the LED and control line (with resistor) to the button via the header. I’ve programmed mine such that it immediately puts the controller chip back into latching mode by reading the LED state and simulating a button press if necessary. Obviously YMMV based on your application. I really wish there was an easier way to handle the latching/inching mode and it sure would be nice to pull RX/TX off the daughter board. The larger header on the other side of the relay doesn’t seem to have anything useful routed, only two pins seem to be routed at all.

5

You can set the relay time on if you use tasmota on the sonoff devices