Counter Type Identification: Eliminate Possibilities by Bit-Change Count
Identifying an unknown counter's architecture from its output sequence is a standard debugging technique when reverse-engineering undocumented digital systems.
A logic analyzer captures an 8-state sequence from an unknown 3-bit counter. The sequence is 000, 001, 011, 010, 110, 111, 101, 100. This sequence repeats continuously.
Count the number of bits that change between each adjacent state. Use this bit-change profile to eliminate impossible counter topologies and identify the specific encoding scheme used by this hardware.
Constraints
- The counter is a synchronous 3-bit state machine.
- The sequence wraps around continuously from the final state back to the initial state.
- Assume all flip-flops trigger on the same clock edge.
Topics
Solve this problem
Place the gates, wire them up and watch the signals settle. Every submission runs on the same simulation engine that grades it.
This problem is part of Codiode Pro. The statement above is free to read.
The circuit builder and code editor need a desktop screen. On a phone, read the problem here and open it on a laptop to solve.