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// vim: ts=4 sw=4 noexpandtab
/*
* Edge detection
*
* Copyright (c) 2019 Michael Buesch <m@bues.ch>
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
`ifndef EDGE_DETECT_MOD_V_
`define EDGE_DETECT_MOD_V_
module edge_detect #(
parameter NR_BITS = 1, /* Number of bits */
) (
input wire clk, /* Clock */
input wire [NR_BITS - 1 : 0] signal, /* Input signal */
output wire [NR_BITS - 1 : 0] rising, /* Rising edge detected on input signal */
output wire [NR_BITS - 1 : 0] falling, /* Falling edge detected on input signal */
);
reg [NR_BITS - 1 : 0] prev_signal;
always @(posedge clk) begin
prev_signal <= signal;
end
assign rising = ~prev_signal & signal;
assign falling = prev_signal & ~signal;
endmodule
`endif /* EDGE_DETECT_MOD_V_ */
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