The fixed length format, data echoplex, data sum and dual redundancychecking was adopted in data transmission to avoid the communication errors.
数据传送采用定长格式，及回送和求和双重冗余校验，以确保通信。
2
Lastly, the methods of software redundancy, setting present output state register unit, and setting self checking program to solve the problem of control state being out of order.
对于控制状态失常问题采用软件冗余、设置当前输出状态寄存单元和设置自检程序等对策。
3
Double mode redundancy structure can be used in the design. The author gives the software program diagram of fault checking.