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.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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//
// ============================================================================
//
import mpmc9_pkg::*;

module mpmc9_app_cmd_gen(clk, state, cmd);
input clk;
input [3:0] state;
output reg [2:0] cmd;

// Strangely, for the DDR3 the default is to have a write command value,
// overridden when a read is needed. The command is processed by the 
// WRITE_DATAx states.

always_ff @(posedge clk)
begin
        if (state==IDLE)
                cmd <= CMD_WRITE;
        else if (state==READ_DATA0)
                cmd <= CMD_READ;
end

endmodule