Subversion Repositories mpmc8

`timescale 1ns / 1ps

// ============================================================================

//        __

//   \\__/ o\    (C) 2015-2022  Robert Finch, Waterloo

//    \  __ /    All rights reserved.

//     \/_//     robfinch@finitron.ca

//       ||

//

// BSD 3-Clause License

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// modification, are permitted provided that the following conditions are met:

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// 1. Redistributions of source code must retain the above copyright notice, this

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// ============================================================================

//

import mpmc10_pkg::*;

module mpmc10_mask_select(rst, clk, state, wmask, mask, mask2);

input rst;

input clk;

input mpmc10_state_t state;

input [15:0] wmask;

output reg [15:0] mask;

output reg [15:0] mask2;

// Setting the data mask. Values are enabled when the data mask is zero.

always_ff @(posedge clk)

if (rst)

  mask2 <= 16'h0000;

else begin

        if (state==PRESET2)

                mask2 <= wmask;

        // For RMW cycle all bytes are writtten.

        else if (state==WRITE_TRAMP1)

                mask2 <= 16'h0000;

end

always_ff @(posedge clk)

if (rst)

  mask <= 16'h0000;

else begin

        if (state==PRESET3)

                mask <= mask2;

end

endmodule