# state encoding techniques

One-Hot encoding: Each state is represented by a bit flip-flop). If there are four states then it requires four bits (four flip-flops) to represent the current state. The valid state values are 1000, 0100, 0010, and 0001. If the value is 0100, then it means second state is the current state.

One-Cold encoding: Same as one-hot encoding except that ‘0’ is the valid value. If there are four states then it requires four bits (four flip-flops) to represent the current state. The valid state values are 0111, 1011, 1101, and 1110.

Binary encoding: Each state is represented by a binary code. A FSM having ‘2 power N’ states requires only N flip-flops.

Gray encoding: Each state is represented by a Gray code. A FSM having ‘2 power N’ states requires only N flip-flops.