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// This is a component of pluto_servo, a PWM servo driver and quadrature
// counter for emc2
// Copyright 2006 Jeff Epler <jepler@unpythonic.net>
//
// 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
module wdt(clk, ena, cnt, out);
input clk, ena, cnt;
output out;
reg [6:0] timer;
wire timer_top = (timer == 7'd127);
reg internal_enable;
wire out = internal_enable && timer_top;
always @(posedge clk) begin
if(ena) begin
internal_enable <= 1;
timer <= 0;
end else if(cnt && !timer_top) timer <= timer + 7'd1;
end
endmodule
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