Tri-state buffer

Hi,

I had some question regarding the warning message below:

Warning: Tri-state node (s) do not directly drive top-level pin(s)

è Warning: Converted the fan-out from the tri-state buffer “tribuf” to the node “comb” into an OR gate

When I find the help message it state:

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Tri-state node(s) do not directly drive top-level pin(s)

CAUSE: The design contains tri-state nodes that drive non-tri-state logic, but the chip does not support internal tri-states. As a result, the Quartus II software converts all the tri-state nodes feeding internal logic to an equivalent logic.

For example, in the following design, the fan-out from the node tribuf to the AND gate is converted to an OR gate.

module test1 (input oe1, data1, in, output out, inout bidir);

wire tribuf, tmp;

assign tribuf = oe1 ? data1 : 1'bz;

and(tmp, in, tribuf);

assign bidir = tribuf;

assign out = tmp;

endmodule

ACTION: Avoid this warning by either removing the non-tri-state fan-outs of the affected tri-state nodes or replacing the tri-state nodes with non-tri-state logic.

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From the statement, it stated that it would convert the AND gate to the OR gate, however when used the Netlist-viewer->RTL-viewer for the tribuf, there is no OR gate converted. Where can I see the changes if the warning message had approached?

Thanks in advance for the help

Best regards

ken