Magnetic Linear Encoder with ESP32

[1stooby]

Hi, I am looking for some general guidance to get started on a project.

I am designing and making a stop block that runs along a t-slot for a mitre saw (to make it easy to make repeatable cuts). Initially the tool is manual but i am also playing around with adding a magnetic linear encoder.

I have this encoder and magnetic strip:
aliexpress - LP02

There are a number of these cheapish systems that use the same head.

It works well but i want to connect the encoder head to an ESP32 with a display so I can do a nicer UI and add some other feature. I cant find any specs for this encoder! It has 6 wires out and another ground shield.

White
Green
Black
Yellow
Blue
GND shield

I have seen some code I think will work I just cant figure a sensible way to wire it to the ESP32. I presume it has A and B channels ... Its currently battery powered (2xAA) so I guess 3.3v will be ok.

Any starting points on the wiring would be greatly appreciated.

[1stooby]

https://es.aliexpress.com/item/1005004330043640.html?algo_pvid=ab6522e2-f322-4cf3-a99a-144b61de07dd&algo_exp_id=ab6522e2-f322-4cf3-a99a-144b61de07dd-0&pdp_npi=4@dis!JPY!16918!7106!!!778.00!326.76!@21038e7717138636587244819eca5f!12000028795451405!sea!JP!0!AB&curPageLogUid=x1m5Q28qRy5q&utparam-url=scene:search|query_from:

[Railroader]

You are posting in the English forum but links to a foreign language site...

[ruilviana]

This type of encoder uses 2 parts.
The first is a sensor that reads the position using the capacitive principle.
Ref: Grant Trebbin: Digital Calliper Teardown and Repair

And then sends it to the display unit.

Sending the sensor to the display must probably use some proprietary protocol.

To study how data is sent, you need to do reverse engineering and study the protocol using a logical analyzer like this for example:

https://www.aliexpress.com/item/1005005578276158.html?spm=a2g0o.productlist.main.1.1eadVAmSVAmSgW&algo_pvid=d6a575fe-5d46-4645-9e7a-f00547f3ad8f&algo_exp_id=d6a575fe-5d46-4645-9e7a-f00547f3ad8f-0&pdp_npi=4%40dis!BRL!67.80!67.80!!!67.80!67.80!%402101fb1717138754677034895e7395!12000033623326619!sea!BR!196481394!&curPageLogUid=9hXSlHfcpAIT&utparam-url=scene%3Asearch|query_from%3A

[1stooby]

Ok. Thanks.
I’m not too worried about the signal yet. My understanding is that it is a quadrature encoder. I have found some of examples of code that I can sue to work with that.

My main issue at the moment is the pin outs of the encoder head. Does anyone have any specs on this device, I have searched and searched.

[1stooby]

Sorry, my bad. I’m English but currently based in spain.
https://www.aliexpress.com/item/1005006605038745.html

There are a number of them out there, most of these cheap ones seem to use the exact same sensor head/cable