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Bidirectional Pins and inout

Altera_Forum
Honored Contributor II
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I'm trying to understand how to use bidirectional pins and inout. Simple put I have a verilog code that looks like this 

 

input oe; 

input a; 

output ab; 

inout b; 

 

assign b = (oe) ? a : 1'bz: 

assign ab = b 

 

The intended operation is that 'ab' will get what is on the pad 'ab' either 'a' or what is driving 'ab' when tri-stated. 

 

The seconds part is the top level is a schematic (.bdf). I have used a 'BIDIR' pin connected to the 'ab' and get a compiler warning that the pin tristate that pin 

 

What am I missing or NOT see? 

 

Thanks
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