Subversion Repositories s80186

// Copyright Jamie Iles, 2017
//
// This file is part of s80x86.
//
// s80x86 is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// s80x86 is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with s80x86.  If not, see <http://www.gnu.org/licenses/>.

module LoopCounter(input logic clk,
                   input logic [4:0] count_in,
                   input logic load,
                   input logic next,
                   output logic done);

reg [4:0] count;

assign done = ~|count;

always_ff @(posedge clk)
    if (load)
        count <= count_in;
    else if (next && |count)
        count <= count - 1'b1;

endmodule