Tuya Smart Knob from AliExpress

I’m not convinced. Here it is… my new Tuya Smart Knob from AliExpress. No doubt about it, the device LOOKS good. Press, rotate, press and rotate, long press etc. This handy “Zigbee + Bluetooth low energy” multifunction button looks wonderful at first glance and is supported by Zigbee2MQTT.

Installation was easy enough – undo the single screw on the base and remove the bottom – insert a CR2032 battery, hold in the reset button for 6 seconds with the pin provided – and Zigbee2MQTT accepts the button.

My first job was to RENAME the button to “tuya smart knob” in Zigbee2MQTT. Done. The next was to press the button. It reported “single”. I then double-pressed it and it reported “double”. So far so good.

Rotating the button right or left resulted in “brightness_step_up” and “brightness_step_down”. I then tried a long-press – “hue_move” and on release “hue_stop”. GREAT. Press and rotate “color_temperature_up” and “color_temperature_down” respectively.

But now, pressing the button, for reasons beyond me at the tiime, resulted in “toggle” and double-press returned the same. WHY?

Operation mode reported in Zigbee2MQTT as “command”. I could not figure out how to get back to showing single or double-press.

So stuck with “toggle” – but it gets worse. See that sticker? So, double-sided adhesive sticks on the bottom and on, say a wall. BUT – what if you have to reset the unit due to lost connectivity – maybe Zigbee2MQTT doesn’t recognise it any more… what about when you have to replace the battery? Rip the unit off the wall and remove that pad to get to the reset button and then take a screw out to replace the battery. Well, no – an observant reader in here pointed out that there’s a metal plate in the box – mine was hiding in the box.

Actually there are two handy holes in the bottom for reset and the indicator so you don’t have to remove that screw for a reset at least… but if you look at other typical Zigbee sensors they often have a button on one side (or in the case of wall sockets, long-press the on-off button) to avoid having to take them off the wall for a reset – why not this one? If I were the designer I’ve have made, say, a 20-second-hold for putting the device into pairing mode…

Whenever you rotate the control or press a button, the green light showing out of the bottom lights up – but of course you’ll never see it as it will be stuck on a wall or a bench…. DAFT. Even just sitting on the bench with the handy soft rubber pads – you still can’t see the light.

I tried everything I can think of to get back to outputting “single” and “double” instead of toggle. I tried short pressing “reset” and Zigbee2MQTT stopped talking to the device.. So now the green light was flashing constantly – I thought I’d have to add the device back into Zigbee2MQTT by enabling joining… nope. Then an observant viewer commented that triple-click (I found it has to be a FAST triple-click) switches modes.

I held in the reset button for 6 seconds – and told Zigbee2MQTT to accept new joins. Sure enough the device came back up complete with the name I’d given it earlier. But still showing “toggle” on pressing the button – but wait…

News Flash: Now, while watching in the Zigbee2mqtt web page, If I send mqtt to the device

topic: zigbee2mqtt/tuya-smart-knob/set

payload: {"operation_mode":"event"}

It does something and I get my single/double actions back and “rotate_left”, “rotate right” etc. whereas sending “command” in the payload takes me back to toggle and the lamp-specific outputs. Triple-click, it seems, does the same thing.

Weird, all in and I’m left unsure how useful this is though I’m SURE I’ll find a use for it – just because I have it 🙂