Even number of 0's and 1's X02999

Design a sequential circuit with one binary input and one binary output. The output must be 1 at cycle $i$ when the sequence of inputs read up to cycle $i-1$ contains an even number of 0’s and an even number of 1’s, otherwise the output must be 0.

Here is an example of the behavior of the circuit. Note that the output will always be 1 in the initial cycle, since the empty sequence contains zero 0’s and zero 1’s.

in:   0 1 1 1 0 1 0 0 1 0 0 1 0 1 0
out:  1 0 0 0 0 0 1 0 1 0 0 0 1 0 0

Specification

module even_zeros_ones (in, out, clk, rst);
    input in, clk, rst;
    output out;

Input

• in is the binary input.

• clk is the clock signal

• rst is the synchronous reset signal.

Output

• out is the output that behaves according to the specification.