# overlapping sequence detector

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### overlapping sequence detector

The state diagram of a moore machine for a 101 detector is: The state table for the above diagram: Four states will require two flip flops. A sequence detector accepts as input a string of bits: either 0 or 1. I will give u the step by step explanation of the state diagram. Thanks in advance for your help. I hope that this can help to you to understand better. In a Mealy machine, output depends on the present state and the external input (x). Hence in the diagram, the output is written outside the states, along with inputs. S0 S1 S2 S3 S4 0/0 State Diagrams Sequence detector: detect sequences of 0010 or 0001 Overlapping patterns are allowed Mealy Design Example output: Overlapping patterns are allowed. Example: Sequential system that detects a sequence of 1111: STEP 1:state diagram – Mealy circuit The next state depends on the input and the present state. In Moore u need to declare the outputs there itself in the state. Its output goes to 1 when a target sequence has been detected. Non overlapping detection: Overlapping detection: STEP 2:State table. The codes are 00110001 and 01110011. Moore state require to four states st0,st1,st2,st3 to detect the 101 sequence. Let’s construct the sequence detector for the sequence 101 using both mealy state machine and moore state machine. Moore based sequence detector. Generalised 8-bit sequence detector is used to detect any sequence among 256 sequences of 8 bit. A sequence detector is a sequential state machine. I'm designing a "1011" overlapping sequence detector,using Mealy Model in Verilog. There are two basic types: overlap and non-overlap. A logical 1 output will be generated when either one of two 8-bit code sequences are correctly detected sequentially. In a Moore machine, output depends only on the present state and not dependent on the input (x). A sequence detector is a sequential state machine. System will detect the overlapping sequences for registered sequence. In a sequence detector that allows overlap, the final bits of one sequence can be the start of another sequence. The sequences I need to detect are 0111 0011 and 0100 0010. The FSM that I'm trying to implement is as shown below :- Verilog Module :- `timescale 1ns / 1ps module State diagrams for sequence detectors can be done easily if you do by considering expectations. Converting the state diagram into a state table: (Overlapping detection) Hi, I have to design a sequence detector that accepts overlapping sequences for two 8-bit codes. Figure 3: State diagram for ‘1010’ sequence detector using the Mealy machine (with overlapping) The Verilog implementation of this FSM can be found in Verilog file in the download section. Thanks for A2A! It is supposed to be like this but with 8 bit sequences instead of 4 bit. Hence in the diagram, the output is written with the states. The state diagram of a Mealy machine for a 1010 detector is: Go to the Top. 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