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I'm trying to make a RAM unit more like the RAM you'd find in a PC. It has an 8 bit address input, data is individual bytes read/written to/from an 8 bit IO, and has SET and ENABLE flags.
The problem is, if I connect the basic (default) RAM's output to my Z-buffered output, it complains about not ...

Is there an easy way to copy the circuits I made in one project over to another? It would be annoying to have to recreate all the basic 1 byte adder, 1 byte switch, 1 byte register kind of generic circuits.

Here's the zip of the project. It has a bunch of other simple components, but only Adder and Main were involved in the issue here.

"Input pin x1 of&(9,21) connected to more than one output pin that are not tri state stable"
I get an error like this for each of the pins on the left-most gates in this full adder:
http://i.imgur.com/oRFDHGM.png
It worked fine independently with button inputs and LED outputs. This error only ...