Subversion Repositories mpmc8

`timescale 1ns / 1ps
// ============================================================================
//        __
//   \\__/ o\    (C) 2015-2022  Robert Finch, Waterloo
//    \  __ /    All rights reserved.
//     \/_//     robfinch<remove>@finitron.ca
//       ||
//
// BSD 3-Clause License
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
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// ============================================================================
//
import mpmc9_pkg::*;

module mpmc9_prev_state(clk, state, prev_state);
input clk;
input [3:0] state;
output reg [3:0] prev_state;

always_ff @(posedge clk)
if (state==IDLE)        // We can stay in the idle state as long as we like
        prev_state <= IDLE;
else begin
        if (state!=prev_state)
                prev_state <= state;
end

endmodule