在各种同步时序电路中,只要电路的状态没有全部利用,即存在冗余态(或无效态,或不确定态)时,都有一个自启动问题。无论什么原因(如电源故障、信号干扰等)使电路进入无效态,就可能使电路一直工作在无效态形成的无效循环中。只有重新启动,才会回到有效状态。因此,设计具有冗余态的同步时序电路时,都必须进行自启动检查。若不能自启动,还必须进行重新设计,修改逻辑函数,使其能自启动。检查方法,一般是根据已求得的状态函数求出各 In a variety of synchronous timing circuits, there is a self-starting problem as long as the state of the circuit is not fully utilized, that is, when there is a redundant state (or invalid state, or indeterminate state). No matter what the cause (such as power failure, signal interference, etc.) to make the circuit into the invalid state, it may make the circuit has been working in the invalid cycle of invalid cycle. Only restart, will return to the valid state. Therefore, the design of redundant timing synchronization circuit, must be self-starting check. If you can not start, you must also redesign, modify the logic function, so that it can start. Inspection methods, generally based on the state function has been obtained from each