17 lines
614 B
Coq
17 lines
614 B
Coq
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//------ Module: iopad -----//
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//------ Verilog file: io.v -----//
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//------ Author: Xifan TANG -----//
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module iopad(
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input zin, // Set output to be Z
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input dout, // Data output
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output din, // Data input
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inout pad, // bi-directional pad
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input direction, // enable signal to control direction of iopad
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input direction_inv // enable signal to control direction of iopad
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);
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//----- when direction enabled, the signal is propagated from pad to din
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assign din = direction ? pad : 1'bz;
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//----- when direction is disabled, the signal is propagated from dout to pad
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assign pad = direction ? 1'bz : dout;
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endmodule
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