[RyanN]

Unfortunately, everything looks correct.

The digital inputs work using an internal pullup resistor, an 10K resistor to be precise, in the digital sidecar.

Have you hooked power to the DSC? I'm not sure if the control system is powered on or off in the picture, but it appears to be off. Without power to the DSC, the pullup resistors won't work, and therefore, your output will always be 0.

Next, it's possible, but unlikely, that the limit switch is shorting out. Have you tried to unplug it while running the code. With nothing connected, it should output a HIGH due to the pullup resistor.

Next, try a different port. We had a port go bad for no reason in 2011 right before our unveiling. It was a very familiar scenario. Simply move the limit switch to a different port, or get a new DSC.