Rotary encoder CJMCU-111 module - where is the button pin?

Hi everyone,

I wonder if it’s possible to get a button signal from my CJMCU-111 module. The module only has 4 pins: GND / VCC / GB / GA.
When I press the encoder I feel a “click”, so technically there is a button but I’m missing the button output pin on the module.

The very first return from Google has this note:"With the buttons on the rotary encoder can be reset to its initial state, that starts counting from 0. ".

So the “button” resets the device to the “zero” position.

Paul

The very first return from Google has this note:"With the buttons on the rotary encoder can be reset to its initial state, that starts counting from 0. ".

Yes I see that but it is rubbish. Think about it, in order to reset the count to zero it has to output a count and it doesn’t because it has a quadrature output. After an extensive search I can’t find any schematic of this module, although I can find lots of Amazon pages repeating this nonsense.

From the pictures you can see the basic Encoder has a push button but it seems it is not brought out. I would suggest to the OP to turn over the board and try and see where those connections from the side of the Encoder with only two connectors on it are tracked to. If they don’t go anywhere then the way to access the button is to solder two wires to these two connections.

bump for addition

Hello Arduino people,

I found the schematic of the CJMCU-111 rotary button with 4 pin connector: https://easyeda.com/hogo20/CJMCU-111-rotary-encoder-schematic . It also explains the switch's functionality: "if VCC and GND connect to +5Vdc
when key pressed--> voltage on pin GA goes from 5 to 2.5V".
There's a small piece of source code that polls the button's pins to get the rotation counter working: Arduino Encoder CJMCU-111 - YouTube (See description)

Have fun!

Christian

[Edit]
I built a demo using the CJMCU-111... :smiley: Just uploaded here:

[/Edit]