16 bit 4 way multiplexer failing test.

[Jcart]

I tested this with the built in chip for the 16bit multiplexer, it still throws an error.

-code removed-

I have actually drawn this out and manually run through the numbers and it checks out. What am I missing?

[ivant]

It's almost right. Just check which input you're selecting when sel=01 and when sel=10.

[cadet1620]

This is a common confusion for programmers who are learning hardware.

Bus wires are numbered from right to left. When a bus is carrying a binary number, bus[0] is the least significant bit of the number.

This will make more sense when you get to chapter 2 and arithmetic hardware. You will see that bus[n] contains the 2ⁿ-weighted bit of the number.

--Mark