52 lines
1.0 KiB
Coq
52 lines
1.0 KiB
Coq
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/** This black-boxes an Async Reset
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* Reg.
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*
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* Because Chisel doesn't support
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* parameterized black boxes,
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* we unfortunately have to
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* instantiate a number of these.
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*
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* Do not confuse an asynchronous
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* reset signal with an asynchronously
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* reset reg. You should still
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* properly synchronize your reset
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* deassertion.
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*
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* @param d Data input
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* @param q Data Output
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* @param clk Clock Input
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* @param rst Reset Input
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*
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* @param init Value to write at Reset.
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* This is a constant,
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* but this construction
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* will likely make backend flows
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* and lint tools unhappy.
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*
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*/
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module AsyncResetReg (
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input d,
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output reg q,
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input clk,
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input rst,
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input init);
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always @(posedge clk or posedge rst) begin
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if (rst) begin
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q <= init;
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end else begin
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q <= d;
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end
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end
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endmodule // AsyncResetReg
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