If Tasmotizer showed the flash was successful, then resolder the Tuya TX line to the TYWE2S RX trace if you haven’t already done so. If you still can’t see the Tasmota AP, then try the following:
desolder the trace
connect your serial flasher, and get everything to the flash ready point
use Tasmotizer to first Erase the existing firmware
power off completely / disconnect serial flasher from module
reconnect serial flasher, and reflash Tasmota.bin again
reconnect Tuya to TYWE2S trace, and check for Tasmota AP again.
If none of that helps, then I’m at a loss… maybe something went bad or is damaged.
It comes from whatever the TuyaMCU expects to see. In Post#2 he talks about watching the weblog in Tasmota console (after entering TuyaMCA 21,2. It will spit out the values that the MCU is using.
I am no longer using Tasmota b/c I was unable to get the LED mod that I did (backlight LED hardware mod attached to GPIO4) to work as a proper PWM LED with the TUYA instruction set at the same time.
But as I recall I used the 10,1000 setting and it worked fine. Maybe @Technowizard can shed some light.
Travis over on DigiBlur does a walkthru of a TuyaMCU setup in Tasmota.
Every Tuya based dimmer has a different dimmer range.
This. It’s been a while since I tinkered with this, but IIRC if you set Web log to 4, you can press the dimmer buttons up and down to see that the Tuya MCU is sending command data for 000003E8 (decimal 1000) @ max, and 0000000A (decimal 10) @ min. Since the Tuya MCU is ultimately what’s in charge, we have to speak to it in the manner it expects… which just happens to make the range on “this switch” 10 to 1000. Like @flynmoose said, every Tuya device is potentially different.
This method still works fine if you want to do the GPIO4 → backlight LED mod and makes it easy to get to the setting. You just get two exposed dimmers in HA.
But I’ve migrated to Tasmota and fought with this for a while.
I finally figured out how to do it. TuyaMCU on Tasmota is strange when it comes to having a separate PWM dimmer for the LED from the dimmer for the mains power.
Has anyone had an issue where they can’t connect to the switch via Wifi after resoldering?
I flash successfully, connect to Tasmota while still attached to my FTDI rig, set the wifi credentials. Reboot and successfully connect to Tasmota with the new IP address. Once I resolder to the board, I can’t connect(yes IP is correct and static). I can unsolder & connect via wifi once again but when I resolder, it won’t connect.
Any thoughts here?
UPDATE: Turns out my re-soldering must have been bad. Wrecked two boards and two chips. The other 14 went well though after I reduced the amount of solder I was using.
Yeah something like that would make it a bit easier if you don’t have a 2nd set of hands around to help. I’m glad my approach to flashing these modules is helping you… just make sure to heed my warning several posts back about the smd cap located just inside that lid opening. Patience and a gentle hand is the key to 100% success rate!
Your guidance on this method has been very valuable, @Technowizard . Thank you.
I hadn’t actually seen your warning, so I appreciate you pointing it out. I flashed 6 switches over the weekend with fairly-intentional carefree cover removal. None of the traces or components were affected. I might have been lucky, but it seems to me that if you keep the tips of the tools away from the components and PCB and use a rocking motion to fatigue the remaining solder joints after peeling off the top of the cover, damage is unlikely. Albeit I was willing to live with less than a 100% success rate since I found the switches for $8 CAD each.
I thought I should post of a recent experience I had with these dimmers. I was cruising through my local costco and checking out all the electronics while my wife shopped as per usual and I noticed a whole display of dimmers sitting in a cardboard display case on the floor. Upon looking at the shelf above them I noticed 3 of the exact 2 packs described at the beginning of this thread with a paper label stuck on them for $20 per pack ($10 per switch). I bought all 3 packs hoping they were old and had not gotten the upgraded firmware. I was lucky and was able to use tuya-convert on all 6 switches directly and import them directly into HomeAssistant. They seem to work great with my ecosmart home depot BR30 LED bulbs. I’ve not installed them in the wall yet, but on bench testing all 6 have worked beautifully and thanks to all the hard work put in by others I was able to get these converted super quickly. I wanted to paste a high level overview for others to follow below. This assumes a bunch of things, including that you have a working MQTT, Home assistant, minimal knowledge of networking/linux, a Raspberry pi 3 or equivalent laying around, and critically that you have unpatched switches that still have the firmware “bug”. Below is the process I put together in case its helpful to anyone to understand the high level flow of how to get these working.
setup RPI3 with raspbian
download tuya-convert from github onto RPI3
run ./start_flash.sh from tuya-convert on RPI3
connect smart phone to vtrust-flash wifi
connect dimmer to power as per instructions included with dimmer
hold button down on dimmer for 5 seconds
hit enter on RPI3 to start flashing
select tasmota on RPI3 to flash to switch
connect smart phone to tasmota_xxxxxx-xxxx wifi access point
use browser on phone to access http://192.168.4.1
enter home wifi SSID and password then click save
switch now connects to home wifi. find its IP (from router or dhcp server and connect to it with browser)
on tasmota main screen click “firmware upgrade” then click “start upgrade”
on tasmota main menu go to “configuration” then “configure module”. In “Module Type” drop down select “Tuya MCU (54)” and click save
on tasmota main menu go to “configuration” then “configure mqtt”. set mqtt server in “host” field and username and password if needed
on tasmota main menu go to “console”. In the “enter command” box type the following 3 commands one after another hitting enter after each
“TuyaMCU 21,2”
“DimmerRange 10,1000”
“SetOption59 1”
Load “tasmota” integration in home assistant and switches will show up in HA automatically
renamed switches as needed through tasmota web inteface by going to “configuration” then “configure other” then change “Device name” and “Friendly name”
Guys I bought one and got it today, it’s entirely different on the inside. Also, some of the instructions for htis device somewhere had us serial flashing it, not sure if this thread is only for tuya convert which doesn’t seem supported anymore anyway
I tried both sets of pins, I did not try cutting the trace. Neither set got anything intelligible from the serial port. Also, nothing seemed to initialize the flashing mode
Looks like the newer batches use the Beken BK7231N chipset. It should still work with ESPHome using the LibreTiny platform. But I’m guessing nobody figured out the GPIOs for this board yet.
