Even Digits

Design a hardware module that finds numbers with only even digits (0,2,4,6,8) within a given range [A,B]. The module should efficiently count and optionally enumerate all such numbers in the range, optimizing for parallel digit processing.

Example: For N=42, find count of numbers with only even digits (0,2,4,6,8) from 1 to 42. Numbers like 2, 4, 6, 8, 20, 22, 24, 26, 28, 40, 42.

Source: Google Kickstart 2018 Round A - Problem A: Even Digits