Illegal reference to net "ack".怎么解决这个问题？

cC追Cc

用modelsim仿真，ack是我定义的reg， 在compile时显示ack<=0这一句出现错误，提示内容如标题，请问下大侠们这是什么情况啊？

gaurson

ack<=0这一句话放在什么地方的？

dengtyu

应该把代码附上

攸牧

module ls245(d, a0, a1, a2, a3, b0, b1, b2, b3);

input d;
inout a0;
inout a1;
inout a2;
inout a3;
inout b0;
inout b1;
inout b2;
inout b3;

reg a0,a1,a2,a3,b0,b1,b2,b3;
wire d;

always@(d or a0 or a1 or a2 or a3 or b0 or b1 or b2 or b3)

    if(d)
         begin
         a0=b0;
         a1=b1;
         a2=b2;
         a3=b3;
         end
         else if(!d)
         begin
         b0=a0;
         b1=a1;
         b2=a2;
         b3=a3;
         end
         else
    begin
         a0=0;
         a1=0;
         a2=0;
         a3=0;
         b0=0;
         b1=0;
         b2=0;
         b3=0;
    end
endmodule

仿真提示错误
# ** Error: E:/shiyan/18.04/t3/ls245.v(21): (vlog-2110) Illegal reference to net "a0".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(22): (vlog-2110) Illegal reference to net "a1".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(23): (vlog-2110) Illegal reference to net "a2".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(24): (vlog-2110) Illegal reference to net "a3".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(28): (vlog-2110) Illegal reference to net "b0".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(29): (vlog-2110) Illegal reference to net "b1".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(30): (vlog-2110) Illegal reference to net "b2".
#
# ** Error: E:/shiyan/18.04/t3/ls245.v(31): (vlog-2110) Illegal reference to net "b3".
该怎么改？

yvhksovo

首先～inout不能定义为reg类型；
其次单bit的d信号只能表示两种状态；怎么写出三个分支的哦；

如果你是想实现三态门的写法的话，参考这个http://blog.sina.com.cn/s/blog_7bf0c30f0100tedd.html

yvhksovo

http://blog.sina.com.cn/s/blog_7bf0c30f0100tedd.html
你是向实现三态门么？


inout不能写成reg类型的