f4pga-examples/xc7/timer/timer.sv

33 lines
651 B
Systemverilog

`timescale 1ns / 1ps
`default_nettype none
module timer #(parameter MOD_VALUE=1000000) (
input wire logic clk, reset, increment,
output logic rolling_over,
output logic[23:0] count = 0
);
always_ff @(posedge clk)
begin
if(reset)
count <= 0;
else if(increment)
begin
if(rolling_over)
count <= 0;
else
count <= count + 1'b1;
end
end
always_comb
begin
if(increment && (count==MOD_VALUE-1))
rolling_over = 1'b1;
else
rolling_over = 1'b0;
end
endmodule