Harrison M280 CNC Lathe, Setting up Threading using phototransistor

Hello, I'm setting up my CNC Lathe, currently using a Mesa 7i76E and Zotac Zbox mini PC. I have a question regarding adding a spindle encoder, I'm currently using two Omron EE-SX1096-W11 and a wheel with 50 holes. This is what was originally on the machine. So now I need to hook up the 2 phototransistors to the Mesa board, should be pretty straight forward, but after looking at the spec sheet on these encoders I see that I will need to use resistors. I'm listening to any and all advice. I've searched around online and most people seem to use a rotary encoder that makes things a lot simpler.

Thanks!

Links to the spec sheets.
Phototransistor www.digikey.com/en/products/detail/omron...E-SX1096-W11/5864619
Mesa 7i76EMesa 7i76E

You need a current limiting resistor for the LED (say 180 Ohm for about 20 mA LED current) You don't need pull-up resistors as these are built into the 7I76E

So (for 'A')

+5V --> 180 Ohm resistor --> LED Anode --> LED Cathode --> GND
7I76E 'A' --> Transistor collector --> Transistor emitter --> GND

Thank you so much! This is exactly what I was looking for. Have a great day.

There is one of those in a workshop at work, proudly bearing the label that it was converted from CNC to manual by the apprentices. Which always struck me as an odd project.

What steppers / drivers does it have? I might have a set of spares (untested)

andypugh wrote: There is one of those in a workshop at work, proudly bearing the label that it was converted from CNC to manual by the apprentices. Which always struck me as an odd project.

What steppers / drivers does it have? I might have a set of spares (untested)

For clarity, there is actually no connection between these facts. Which is why I am not sure that the drivers I have are from a Harrison.

Hi Andy, I removed the original control board, I felt like it would have been far more involved that simply gutting it and starting fresh. I'm currently using DM860A and DM556 drivers for the Z and X axis respectively. I've been struggling to setup the encoder signal going into the Mesa card and Linuxcnc. I followed the standard Mesa 7I76E wiring diagram and configured the spindle encoder using PNC config. I have attached my Hal file as well, I'm not seeing the connection to the pins on TB3 in the Hal file. It feels like I am so close to having this all up and running.