[Solved] 6-bit Full Adder returns with an error [closed]

Question

In your adder6 declaration have this line:

adder4 a(.sum([3:0]),c_o[0],.a(a[3:0]), .b(b[3:0),c_in); //4-bits adder

As you can see, you’ve called an instance of adder4 a. At the same time, you’ve called an input port a. That’s why you’re getting an error when trying to compile your code. The easiest solution would be to rename an adder4 instance.

Btw that particular line should look a little bit different in case to work:

adder4 add(.sum(sum[3:0]), .c_out(c_o[0]), .a(a[3:0]), .b(b[3:0]), .c_in(c_in));

Accepted Answer

In your adder6 declaration have this line:

adder4 a(.sum([3:0]),c_o[0],.a(a[3:0]), .b(b[3:0),c_in); //4-bits adder

As you can see, you’ve called an instance of adder4 a. At the same time, you’ve called an input port a. That’s why you’re getting an error when trying to compile your code. The easiest solution would be to rename an adder4 instance.

Btw that particular line should look a little bit different in case to work:

adder4 add(.sum(sum[3:0]), .c_out(c_o[0]), .a(a[3:0]), .b(b[3:0]), .c_in(c_in));