List of Messages |
module test1 (input data, oe, output out, inout bidir); wire triwire, gnd; assign gnd = 1'b0; assign triwire = oe ? gnd : 1'bz; and(out, triwire, data); assign bidir = triwire; endmoduleIn this design, the open-drain buffer triwire feeds an AND gate in addition to feeding the pin bidir. As a result, the Quartus Prime software converts its fan-out to the AND gate to a wire, and gives this warning. Note that an inversion is also considered an internal fan-out. As a result, the Quartus Prime software converts an open-drain buffer invertedly feeding a pin to a wire. Additionally, if an open-drain buffer feeds another open-drain buffer, the Quartus Prime software converts the first open-drain buffer to a wire. See the sub-messages below to view a list of the affected nodes.
ACTION: Avoid this warning message by removing all the internal fan-outs of the open-drain buffers.
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