lecture 8 mealy and moore machines.pptx
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Lecture 8 Mealy and Moore Machines.pptxTRANSCRIPT
Mealy Machines & Moore Machines
VLSI Circuits & Systems
Lecture 8Mealy and Moore MachinesMealy Machine
Characterized by Outputs are a function of both inputs and current state9/26/20082ECE 561 - Lecture 4
Moore machine
Characterized by Outputs are a function current state only
9/26/20083ECE 561 - Lecture 4
Difference b/w Mealy & Moore Machines
Example 3Ahmad Almulhem, KFUPM 2010Problem: Design of A Sequence Recognizer Design a Moore machine to detect the sequence (111). The circuit has one input (X) and one output (Z).Example 3 (cont.)Ahmad Almulhem, KFUPM 2010Step1: State Diagram Sequence to be detected:111S0/0S1/0S2/0S3/110110001Example 3 (cont.)Ahmad Almulhem, KFUPM 2010Step2: State TableUse binary encodingUse JK-FF and D-FF
S0/0S1/0S2/0S3/110110001Example 3 (cont.)Ahmad Almulhem, KFUPM 2010Step4: Draw CircuitFor step3, use k-maps as usual
JA = XBKA = XDB = X(A+B)Z = A.BDraw a Moore circuit to detect 110 sequence.Design a Moore circuit which gives output z=1 if three consecutives 1 but z=0 if 4 or more consecutive 1 occurs.Prepared by Shiraz HusainDesign a Moore sequential network that has one input and one output. When it recieves 011, z=1 and remains 1 until second time 011 occurs after this output becomes 0 and remains 0 until next time 011 occurs and so on.Prepared by Shiraz HusainNextStateLogic
OutputLogic
StateMemory(F/F)
CLOCK
Inputs
Excitation
CurrentState
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NextStateLogic
OutputLogic
StateMemory(F/F)
CLOCK
Inputs
Excitation
CurrentState
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