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Joseph Puzzo@josephpuzzo· 473 viewsin General Discussion

Why are the limit switches not set up to use pullup?

Hi! So It seems each limit switch requires three wires when you can instead achieve the same via the internal pullup resistors in the teensy. See attached image and this link http://johnny-five.io/examples/button-pullup/ Why did you decide to use three wires instead of two ?

johnny-five.io

johnny-five.io/examples/button-pullup/

Comment 2

Joseph Puzzo

Ahh Ok that makes sense thanks !

Chris Annin

The pull-up resistors weren't strong enough to be reliable over a 5 ft ethernet cable, so I opted to do three wires and pull it to ground when the switch is not made. This ended up being the most bulletproof solution that I have found.

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