Good afternoon;

I am working on a 8 bit calculator for school (the beginning stages). Right now we are making a 4x1 mux that takes in 4 bit input and send a 4 bit output. I have a 1 bit 4 by one mux set up in logism. However; this is where I get stuck. my notes say create 2 2x1 mux's to make a 4x1. I have tried several ways and can't get the right output. I only get the right output when I have 8 inputs. However, the assignment requires only 4 inputs. I would appreciate insight as to how to create this circuit.

Thank you

 

Welcome to AAC!

Right now we are making a 4x1 mux that takes in 4 bit input and send a 4 bit output.

By definition, a 4:1 mux has 4 inputs, 2 control inputs, and one output.

Please post schematics for the circuits you're referencing.

As this is homework, forum guidelines are to provide guidance, but not answers. You need to show us your best efforts so we can see where you're going astray.

 

Of course, completely understood. I have included my designs. I have attempted increasing the bit flow but it doesn't work due to the signal bits need to be just one bit.

Welcome to AAC!
By definition, a 4:1 mux has 4 inputs, 2 control inputs, and one output.

Please post schematics for the circuits you're referencing.

As this is homework, forum guidelines are to provide guidance, but not answers. You need to show us your best efforts so we can see where you're going astray.

 

However; this is where I get stuck. my notes say create 2 2x1 mux's to make a 4x1.

Kindly label the images in post #3 so we can better understand what you're trying to show us.

 

Sorry about that. I attached a .doc that has a breakdown of each image including the image. If you need more please let me know. I appreciate the time.

 

However; this is where I get stuck. my notes say create 2 2x1 mux's to make a 4x1.

I don't see where you're trying to implement a 4:1 mux using 2:1 muxes; and I don't think you can do it with just 2.

EDIT: Relevant images from the docx file:

 

Yea that is where I am stuck. I don't know the process on how to do that? Do we attach the output of the 2x1 into the inputs of the 4x1? Is it the other way around?

 

Yea that is where I am stuck. I don't know the process on how to do that? Do we attach the output of the 2x1 into the inputs of the 4x1? Is it the other way around?

I'd seek clarification of the instructions.

If you wanted to make a 4 input AND gate and only had 2 input AND gates, you could do it, but you can't do it with just 2 of the 2 input gates.