用程序实现状态机功能，有限状态机是指输出取决于过去输入部分和当前输入部分的时序逻辑电路。一般来说，除了输入部分和输出部分外，有限状态机还含有一组具有“记忆”功能的寄存器，这些寄存器的功能是记忆有限状态机的内部状态，它们常被称为状态寄存器。在有限状态机中，状态寄存器的的下一个状态不仅与输入信号有关，而且还与该寄存器的当前状态有关，因此有限状态机又可以认为是组合逻辑和寄存器逻辑的一种组合。其中，寄存器逻辑的功能是存储有限状态机的内部状态；而组合逻辑有可以分为次态逻辑和输出逻辑两部分，次态逻辑的功能是确定有限状态机的下一个状态，输出逻辑的功能是确定有限状态机的输出。

-Finite state machine is refers to the output depends on the past input part and the current input portion of temporal logic circuit. Generally speaking, besides input part and output part outside, finite state machine still contain a group has "memory" register, and these registers functions is the function of memory finite state machine internal state, they often called status register. In a finite state machine, status register of the next state not only with the input signal, but also on the current state of the register with the relevant, so a finite state machine and can think of is the combination of a kind of logic and registers logical combinations. Among them, the function is storing registers logic finite state machine internal state, And the assembly logic can be divided into minor state has two parts, logic and output logical logic function is minor state determinate finite state machine next state, output logic function is to determine the finite state machine s output.