Subversion Repositories mpmc8

`timescale 1ns / 1ps

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

//        __

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

//    \  __ /    All rights reserved.

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

//       ||

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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