:PROPERTIES: :ID: b9c2956a-ac68-4904-b276-0e8fb87b4ef8 :mtime: 20231020031555 20231018034708 :ctime: 20231018034648 :END: #+title: synchronous counter #+filetags: :public:project: * Synchrous counter A synchronous counter is a type of [[id:ddd7853a-3ffa-469e-bb2b-799189379141][synchronous circuit]]. It is an [[id:eb73ecc4-1c5a-4e40-90c2-112c61f0e8e8][counter circuit]] where all the flip-flops are conencted to the [[id:124ef912-c3fd-4fbf-98df-fc0677c8f534][computer clock]]. * Example of a Synchronous Counter * Example: 0-7 counter using 3 [[id:b536582a-66cc-4239-801f-6136ab4b919d][flip-flops]] | Q_2 | Q_1 | Q_0 | Q_2' | Q_1' | Q_0' | D_2 | D_1 | D_0 | |-----+-----+-----+------+------+------+-----+-----+-----| | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 1 | | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | For a 0 to 7 counter, 3 D-type FFs are needed The procedure is to: Write down the desired count sequence in the current state columns Write down the required next states in the next state columns Fill in the FF inputs required to give the defined next state Note: Since (or ) for a D-FF, the required FF inputs are identical to the Next state