verilog数字系统设计教程 所有例题的源程

				//?????
				//--------------------------------------------------------------------
				module datactl (data,in,data_ena);
				output [7:0]data;
				input [7:0]in;
				input data_ena;
				
				assign  data = (data_ena)? in : 8'bzzzz_zzzz;
				
				endmodule
				//--------------------------------------------------------------------