bidirectional buffer implementation

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By reading a buffer, you only get the internal driving signal state.

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Thanks for pointing this out. FvM brings up an interesting point. I always thought it was the output that was being "fed-back" and read before it goes out to the pin. But anyway, you're probably right that it's the input to the buffer that gets read.

I guess I'll have to agree that a "buffer" is actually an output (that provides some feedback feature), and cannot be used as a bidirectional pin. I forgot the fact that you can't use a "buffer" to read an external signal driven by another device - this means it synthesizes to only 1 output buffer instead of 2 buffers going in and out for bidirs. You can only use it to read back what you've sent out. So again... thanks FvM for strobing my memory after being stuck in idle for too long.