典型的状态机，简单的状态机可以不需要编码，也可以采用one-hot编码方式，如果状态很多时，采用格雷码，能有效避免亚稳态。-A typical state machine, a simple state machine can do without coding, can also be used one-hot encoding, if the state in many cases, the use of Gray code, can effectively avoid metastable.