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What does this Eagle PCB creator error mean?

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HexInverter

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First off, hello! This is my first post on the forums, though I have lurked on here quite a few times (never really getting around to registering until now).

I am a bit of an Eagle PCB noob (as well as an electronics novice), and am running into an issue. I've created a fairly straight forward schematic using a CD4093 Quad NAND gate which only uses 3 of the 4 input/output stages. The inputs of the 3 stages are using feedback loop resistor/capacitors on one input, and the other one is connected to the +9v supply. I have my supply wired properly, as was checked in the PCB layout - however I'm still getting an error for Gate D - the one I'm not using: "Part IC1 has uninvoked gate D with unconnected input pin I0" and "Part IC1 has uninvoked gate D with unconnected input pin I1"

I know this circuit works on the breadboard for what I need it to do...oscillate :) but, I'd like to understand what this error message means and how to make Eagle happy with it, or whether it's necessary or not. I started my crash course in Eagle a couple days ago, and so far have learned that it's not the most intuitive program (although it seems to be extremely capable once you get the hang of it) - so I was hoping someone could debunk this for me!

It's probably a silly thing that my being new to electronics has caused me to overlook (I was thinking maybe that it expects power to it regardless of it being used, and that there's some way to bypass it)...but I'm not 100% sure.

Thanks for any help! :)
 
It has been good practice to connect unused CMOS inputs either to VDD or VSS, since they might cause erroneous behaviour of the used gates.

So Eagle assumes you connect even unused gates somewhere.

Invoke the unused gate and connect both inputs either to VDD or VSS (whichever is more practicable for routing) and make Eagle H A P P Y
.

Boncuk
 
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