# overlapping sequence detector

04.12.2020Uncategorized

Overlapping patterns are allowed. Sequence detector with overlapping. System will detect the overlapping sequences for registered sequence. Converting the state diagram into a state table: (Overlapping detection) A sequence detector is a sequential state machine. I will give u the step by step explanation of the state diagram. Thanks for A2A! Generalised 8-bit sequence detector is used to detect any sequence among 256 sequences of 8 bit. In Moore u need to declare the outputs there itself in the state. Hi, I have to design a sequence detector that accepts overlapping sequences for two 8-bit codes. Let’s construct the sequence detector for the sequence 101 using both mealy state machine and moore state machine. The FSM that I'm trying to implement is as shown below :- Verilog Module :- `timescale 1ns / 1ps module Its output goes to 1 when a target sequence has been detected. Moore state require to four states st0,st1,st2,st3 to detect the 101 sequence. Hence in the diagram, the output is written with the states. 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 in advance for your help. A sequence detector accepts as input a string of bits: either 0 or 1. It is supposed to be like this but with 8 bit sequences instead of 4 bit. There are two basic types: overlap and non-overlap. The codes are 00110001 and 01110011. Non overlapping detection: Overlapping detection: STEP 2:State table. Moore based sequence detector. A sequence detector is a sequential state machine. I'm designing a "1011" overlapping sequence detector,using Mealy Model in Verilog. 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. Go to the Top. The state diagram of a Mealy machine for a 1010 detector is: I hope that this can help to you to understand better. Hence in the diagram, the output is written outside the states, along with inputs. 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). Mealy state machine require only three states st0,st1,st2 to detect the 101 sequence. State diagrams for sequence detectors can be done easily if you do by considering expectations. In a sequence detector that allows overlap, the final bits of one sequence can be the start of another sequence. 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. In a Mealy machine, output depends on the present state and the external input (x). The sequences I need to detect are 0111 0011 and 0100 0010. 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