what is the truth table of mux4way16?

[moonwalk]

sel    decimal v
0 0 0 a
0 1 1 b
1 0 2 c
1 1 3 d

when i tried to work out the boolean algebra expression, i realized it was hard to assign a 1 or 0 value to the letters as a, b, c, d like before. Besides, the sel pin has two values, and when we input, shall we input the binary or decimal value for sel?
I feel very confused and have no clue at all.
could somebody give me a hint and direct me to the right way? I feel I have a wrong understanding of something.
Thanks!

[cadet1620]

One approach for Mux4Way16 is to design Mux4Way (single bit) and put 16 of them into Mux4Way16.

The Mux4Way has 6 inputs: sel0, sel1, a, b, c, d, so there are 2^6=64 lines in the truth table and the Karnaugh map will be 8 by 8. This is too big to easily do by hand, so a different approach is needed.

One of the goals of this course is to learn how to use abstraction. Since you just made Mux16, think about how you can use some Mux16s to make Mux4Way16.

It might be easier to first think about how to make DeMux4Way from DeMuxs.

--Mark

[moonwalk]

Many Thanks! I got it!
The key is to know the input of sel is decimal and make use of its binary form and features of mux16 chips to divide a, b, c, d into different groups!

Thanks again!