Connecting the Rev Magnetic Limit switch to the CTRE Mag encoder pads

Has anyone successfully and can share how to connect Rev Robotics or any other magnetic Limit switch to the CTRE Limit inputs. In our case the Solder pads on a CTRE Magnetic Encoder. It seem to me that we Need a 3 or 5 vdc source to get things working.

It needs power (Red wire, 3.3 to 5 Volt), ground (black wire), and provides a digital output (White and blue, wired together internally, according to the data sheet). It has an internal pull-up resistor.
CTRE motor driver: get power from pin 1 (3.3 Volts to the red wire), pin 10 for ground (black wire), and then wire either the white or blue wires to the limit you want (pins 4 or 8). That should do it. You could instead use power from pin 2 (5 Volts); I don’t think it will make much difference. I am a bit mystified why they used a blue LED; those take more voltage than just about any other LED…

I haven’t actually used it, but I’m fluent in “electronics” and “sensors” :wink:

It’s an extension of the simple Computer Light Performance Enhancement Theory:

Red LED = Goes faster
Blue LED = Runs cooler
Green LED = More energy efficient

Soldering to the pins on the small 10-pin connector is tough.

There’s a related discussion here: Connecting a Magnetic Encoder and a Hall Effect to TalonSrx.

I have seen that thread. Short answer is the effort to make it work out weighs just using a hard switch

Oh, sorry, should have mentioned it. There’s a couple different nice little breakout boards available for hooking stuff up to the CTRE drivers, or you can cut a grey cable and solder to the wires. You really don’t want to try to solder into that fiddly little insulation displacement connector!!!

I’ve used this one to good effect for several projects. You can solder directly to it, or use pins and Dupont connectors.

http://www.ctr-electronics.com/net-gadgeteer/breakoutmodule.html

All good ideas but our issue is we are using the MagEncoder as well on this device. We ended up making a flag and used a mechanical switch.

Something you might want to check out for the future:

Littlefuse sells magnetic proximity sensors in a variety of different mounting options.

I like these threaded ones as you can easily adjust the spacing from the magnet by adjusting some nuts. They’re cheap too, so worth having a few on hand. Cart filler for the next PDV.

https://www.digikey.com/short/11jvd0dm

Just a two wire contact closure. Should be a drop in replacement for a mechanical limit switch.
These have been out go to for end of travel /position indications for the past ~4 years

They also make the lower profile rectangular ones in the same product category.

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