One of my old insteon switches died a few days ago so I had to replace it and I decided to give those cheap costco wifi switches a try:
This 3 pack was 38,99$ CAD at my local costco, so it’s pretty cheap! not even 15$ each. Figured for the price of one Z-wave switch, I would get 3.
I already helped a friend flash one of those cheap devices a couple of months ago using and OTA method with tuya-convert, but it turns out those newer ones are patched and OTA flashing is not an option anynore
I don’t know the exact model number from which the patch is on, but this particular one is patched and I was getting a weird encryption error while trying OTA with tuya-convert. I had some spare time, so I decided to continue digging and soon found out that it is still possible to flash those with a wired method. Not as convenient as OTA, but still, if I could get it to work, it would be great.
So after a lot of reading, I conclued that I had to remove the chip (TYWE2S) to be able to wire it for flashing because one of the required pin (GPIO0) is on the back side of the chip and not accessible. So I opened the switch (pretty easy, just 4 screw) and I used a heat gun to heat the solder points of the chip while prying a little bit on it until it popped out.
I then proceeded to solder some tiny wires to the required points: VCC, GND, TX, TX and GPIO0. All points are labeled (GPIO0 is I00).
Then it was just a matter of using an FTDI dongle that I already had to sometime flash firmwares to my little quadcopters (you could also use an arduino for that). Just make sure your dongle is set to 3.3V, because using 5v would probably damage the chip.
This particular chip needs to be put in flash mode before you can flash it and to do it, you just have to touch GPIO0 to ground when powering it up and release after a few secs, then you can proceed with flashing. So I hooked up GPIO0 to GND using a jumper wire, then connected the usb dongle and removed this jumper wire like 3-4 seconds after connecting usb.
I then used tasmotizer to flash the latest tasmota firmware, there are other firmwares or software to do that, just use whatever you prefer.
and… tada! after that I simply reinstalled the chip on the board using the holes that were already conveniently there, almost like if they knew someone would do this mod…
(I put a small piece of tape under, just to make sure nothing touches the remaining traces under)
After that, I put the switch back together, installed it in the wall and it showed up as an access point to configure, like any normal tasmota device. For now, I just used “Tuya MCU (54)” module in the configuration and it works as a basic switch. I still need to figure the dimmer part, but that’s no big deal for me and it should be fairly easy to find the right config for it now that tasmota is up.
When configured, you can control it using some http requests, so I wrote a pretty basic device handler for it:
So that’s it. Not the easiest mod, but still, not overly complicated if you are not afraid of some simple soldering and you get a nice smart wifi switch integrated with smartthings for less than 15$… not sure you can find a better deal!