Subversion Repositories mpmc8

`timescale 1ns / 1ps
// ============================================================================
//        __
//   \\__/ o\    (C) 2022  Robert Finch, Waterloo
//    \  __ /    All rights reserved.
//     \/_//     robfinch<remove>@finitron.ca
//       ||
//
// BSD 3-Clause License
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// 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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// ============================================================================
//
module mpmc10_chcnt(rst, clk, hit, cnt);
parameter BITS=7;
input rst;
input clk;
input hit;
output reg [BITS-1:0] cnt;

reg hit1;

always_ff @(posedge clk)
if (rst) begin
        cnt <= {1'b1,{BITS-1{1'b0}}};
        hit1 <= 1'b0;
end
else begin
        hit1 <= hit;
        if (hit)
                cnt <= {1'b1,{BITS-1{1'b0}}};
        else if (hit1 & ~hit)   // neg. edge on hit
                cnt <= 'd0;
        else if (!cnt[BITS-1])
                cnt <= cnt + 2'd1;
end

endmodule