if (mode == CLOCK_DISP) begin
					if (KEY[0] == 1'b0) begin
						btn_timer <= btn_timer + 8'd1;
						if (btn_timer == 8'd200) begin
							btn_timer <= 8'd0;
							mode <= CLOCK_SET;
						end
					end else begin
						btn_timer <= 8'd0;
					end
				end