Digital Inputs constantly on high state.

[Ilias98]

Hello to the community,

I have just started working with the RevPi a few days ago and I am still navigating the change from standard Raspberry Pi's to the their big modular sibling. I am trying to follow the tutorials posted on YouTube by KUNBUS and the documentation provided with the revpimodio in order to start manipulating the IOs of my DIO module (my core device is a RevPi Core 3 16GB). So far I have succesfuly managed (using both the piTest tool provided by KUNBUS and some python scripts of mine utilizing revpimodio) to change the state of an output pin from LOW to HIGH to trigger a change to a real world device (in my case a pneumatic valve).

So far so good, but the problem comes in when I am trying to read the state of an input pin. Idealy, I want to hook up a distance sensor to an input pin of the RevPi that will trigger the valve. But, when I try to read the current value of any Input Pin of the DIO is always on HIGH. No mater which pin I try, or if anything is connected to them, they appear to be stuck on HIGH. But when I actually go and measure the voltage on the Input Pins is 0V. I would expect a behaviour similar to what I am seeing on the Tutorial 12, so that whenever I try piTest on an Input Pin the state would be 0 and change to 1 whith an outside stimulation.

Could it be a problem with my configuration of the DIO pins, or do I not properly understand the underlying principal of the DIO pins of the RevPi? I am attaching some pictures of my piCtory, my set up and of the pi terminal to help you understand my problem. Any help would be greatly appreciated. If any clarification is needed feel free to ask for it.

[nicolaiB]

Dear Ilias98,

welcome to the Revolution Pi community!

Please make sure that you have wired the connector X2 according our documentation. In the picture of your setup I can see that the status led of the input section is red. It looks like you forgot to wire the input power connector (I can only see wires to the output power connector).

Nicolai

[Ilias98]

Dear nicolaiB,

I appreciate the immediate response. You were right, my problem is fixed. I appreciate the help.

Cheers.