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Using a Hall Effect sensor as a homing and limit switch for Tic

I want to use the Hall Effect sensor as a homing and limit switch. https://www.sparkfun.com/products/14709
This has three leads – power (VDD), GND, output. Bring a magnet close and the output acts like a switch. If I put a 10K pullup resister between output/VDD, and use a VOM to measure Voltage between output and GND, I get “0” V as the magnet gets close and 5V when the magnet is far away. I think this means that the 0V situation is “open” and the 5V situation is “closed” in the context of a switch. Can someone explain how to wire this to the Tic controller so that it acts as a limit switch?

Hello, Jim.

You can find a detailed explanation for limit and homing switches in the “Setting up limit switches and homing” section of the Tic user’s guide. Based on the behavior you described, you should be able to make the following connections and enable the internal pull-up resistor as explained in that same section of the user’s guide to get it working:

Sensor    Tic
GND   -   GND
VDD   -   5V(out)
output -   SCL, SDA, TX, RX, or RC configured as a limit switch