4.Category of Sequential Circuits(分类) According to the relationship among output O, present state Sm and input I(各变量的关系) *Moore Model(摩尔型电路)：O=fi(S") *Mealy Model(米里型电路)：O=f2(I,S") According to the clock pulse that control the sequential states(CP对各个触发器的控制) *Synchronous:All FFs in the storage circuits are controlled by a uniform CP source. 同步时序电路：各个FF受同一个CP控制. Asynchronous:No such a uniform CP source. 异步时序电路：各F℉没有统一的CP源. 4. Category of Sequential Circuits (分类) ◆According to the relationship among output O, present state Sn and input I (各变量的关系) Moore Model (摩尔型电路): )S(fO n  1 Mealy Model (米里型电路): )S,I(fO n  2 ◆According to the clock pulse that control the sequential states (CP对各个触发器的控制) Synchronous: All FFs in the storage circuits are controlled by a uniform CP source. 同步时序电路：各个FF受同一个CP控制.  Asynchronous: No such a uniform CP source. 异步时序电路：各FF没有统一的CP源