Problem with the ALU

[camelCase]

ALU.hdl
Why do I get the error: Line 56 (The line after the "x+y if f" comment),
Can't connect part's output pin to gate's input pin?

[ybakos]

I believe it's because false is not a 16-bit value, it is a single bit.

[cadet1620]

Mux16(a=false, b=y2, sel=f, out=y_add);

Can't connect part's output pin to gate's input pin: load ALU.hdl

'_' is not a legal character in HDL names. You want to change "y_add" to "yAdd".

Why the strange error message?
The parser saw this as "out=y". "y" is the "gate's input pin" in the message.

--Mark

[camelCase]

Thank you! You are right. After fixing a view little issues I finished my ALU!! Thank you for replying so fast! This book/course has a awesome community :)

[Mike2345]

So how do we represent false as a 16 bit value

[WBahn]

As stated in A.5.3:

" The constants true and false may also be used as buses, in which case the required width is deduced implicitly from the context of the connection."

[Mike2345]

So is there anyway to represent false as a 16 bit

On Sun, Oct 6, 2019, 12:41 AM WBahn [via Nand2Tetris Questions and Answers Forum] <[hidden email]> wrote:

As stated in A.5.3:

" The constants true and false may also be used as buses, in which case the required width is deduced implicitly from the context of the connection."

---

If you reply to this email, your message will be added to the discussion below:

http://nand2tetris-questions-and-answers-forum.32033.n3.nabble.com/Problem-with-the-ALU-tp4031419p4033721.html

To unsubscribe from Problem with the ALU, click here.
NAML

[WBahn]

As it says, the width of false and true, when used as buses, is determined by the width of the context in which they are used.

If you connect 'false' to an input pin that is 16-bits wide, then that particular 'false' is a sixteen-bit wide signal that is hard tied to a logic false.