`timescale 1ns / 1ps module test; reg [63:0] state; reg [79:0] keys; wire [63:0] res; wire clk; // Instantiate a module with a clock and res signal PRESENT inst ( .clk(clk), .res(res) ); initial begin state = 64'h0000000000000000; keys = 80'h00000000000000000000; clk = 0; end always #10 clk = ~clk; initial begin #600 $finish(); end endmodule这段代码的错误是什么

这段代码的错误是在实例化 PRESENT 模块时没有传入 state 和 keys 信号。应该在 PRESENT 模块的端口连接列表中添加对应的信号连接。如下所示：

PRESENT inst (
    .clk(clk),
    .state(state),
    .keys(keys),
    .res(res)
);