21 lines
737 B
Coq
21 lines
737 B
Coq
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//-----------------------------------------------------
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// Design Name : General Purpose I/Os
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// File Name : gpio.v
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// Coder : Xifan TANG
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//-----------------------------------------------------
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//-----------------------------------------------------
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// Function : A minimum general purpose I/O
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//-----------------------------------------------------
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module GPIO (
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input A, // Data output
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output Y, // Data input
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inout PAD, // bi-directional pad
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input DIR // direction control
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);
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//----- when direction enabled, the signal is propagated from PAD to data input
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assign Y = DIR ? PAD : 1'bz;
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//----- when direction is disabled, the signal is propagated from data out to pad
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assign PAD = DIR ? 1'bz : A;
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endmodule
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