Wiring "3-pin" Shaft Encoder.

[Mark McLeod]

Originally Posted by Joel J.

Yes. Thats how it is supposed to be setup. How do we go about porting that to the digital inputs? Should there be a ground connection somewhere? We connected A to the signal of one digital input and B to the signal of another digital input and C to the +5v on the digital input. We are getting a constant 1 as the input of the encoders no matter how many times the wheels rotate (it does not go through each state). I conclude that this is happening as a result of the pin pulling itself to high (since thats how IFI set things up), because its not getting any input, which hints at an improperly wired system. Is this the case?

Yes, I also believe it's the IFI pull-up that's defeating you. It's high when the circuit is open and high when it's closed by the encoder.

You should be able to connect A/B to signal as you are doing and C to ground. Then the digital input will be high when there is no circuit and low when signal is passed through the encoder to ground.