Mux4Way16 Chip

Abstraction and Implementation of 4-way 16-bit Multiplexor Chip in Hardware Design Language and Java™.

Mux4Way16 (4-way 16-bit Multiplexor) Chip

An 4-way 16-bit Multiplexor chip outputs one of the given four 16-bit inputs, which is specified by selector bit.

An m-way n-bit multiplexor selects one of m n-bit input buses and outputs it to a single n-bit output bus. The selection is specified by a set of k control bits, where k = (log m to the base 2).

Unlike n-bit input logic gates, n-way logic gates use the same output iteratively over the boolean operation, which means, it uses the previous output as input for the next similar boolean operation.

Chip name: Mux4Way16
Inputs: a[16], b[16], c[16], d[16], sel[2]
Outputs: out[16]
Function: If sel=00 then out=a 
                else if sel=01 then out=b
                else if sel=10 then out=c
                else if sel=11 then out=d
Comment: The assignment operations mentioned above are all
16-bit. For example, "out=a" means "for i=0..15
out[i]=a[i]".

Abstraction of 4-way 16-bit Multiplexor Chip - Representation and Truth Table

Implementation of Mux4Way16 Chip in HDL

The function in the above abstraction can help in the implementation of Mux4Way16 Chip.

You can use the Mux16 chip that you've built earlier.

CHIP Mux4Way16 {
    IN a[16], b[16], c[16], d[16], sel[2];
    OUT out[16];

    PARTS:
    Mux16(a=a, b=b, sel=sel[0], out=ab);
    Mux16(a=c, b=d, sel=sel[0], out=cd);
    Mux16(a=ab, b=cd, sel=sel[1], out=out);
}

Implementation of Mux4Way16 Chip in Java™

Similar to the Implementation in HDL

package CombChips;

import Misc.Convert;

class Mux4Way16_Gate extends Mux16_Gate {

    protected static int[] Mux4Way16(int[] a, int[] b, int[] c, int[] d, int[] sel) {
                
        int[] arr_a = Convert.Arrayto16(a);
        int[] arr_b = Convert.Arrayto16(b);
        int[] arr_c = Convert.Arrayto16(c);
        int[] arr_d = Convert.Arrayto16(d);
        
        int[] arr_sel = new int[2];
        System.arraycopy(sel, 0, arr_sel, 0, arr_sel.length);

        int[] temp1 = Mux16(arr_a, arr_b, arr_sel[1]);
        int[] temp2 = Mux16(arr_c, arr_d, arr_sel[1]);
        int[] out = Mux16(temp1, temp2, arr_sel[0]);

        return out;
    }
}