题解 | #多功能数据处理器#

`timescale 1ns/1ns
module data_select(
	input clk,
	input rst_n,
	input signed[7:0]a,
	input signed[7:0]b,
	input [1:0]select,
	output reg signed [8:0]c
);

always@(posedge clk or negedge rst_n) begin
    if(rst_n == 1'b0) begin
        c <= 9'd0;
	end
	else begin
        case(select)
		    2'd0: c <= a;
			2'd1: c <= b;
			2'd2: c <= a + b;
			2'd3: c <= a - b;
			default: c <= 9'd0;
		endcase
	end
end

endmodule