Question

You are required to design a sequence detector circuit which detects all non-overlapped instances of the input pattern "10110" in a string of bits coming through an input line X and generates an active high output Y when detected. ) Produce a suitably labeled Moore machine state diagram for this problem. In the design, make sure that there are no missed patterns and explain the choice of number of states, number of bits in the state representation and the choice of the next state transitions in detail. Write a truth table that tabulates the states / transitions of the sequence detector and the output signal. Derive and simplify the Boolean expressions for the next state logic and the output. Sketch and label a schematic diagram that implements your solution using D-type flip flops and your choice of logic gates. Clearly identify the key blocks of the state machine on the diagram. Sketch the timing diagram for the clock, input, current state and output signals for the following input sequence (assume the state machine is reset at the start of the sequence): 10101110110. Assume the input signal is asynchronous and make sure that you correctly align the transitions for the synchronous signals. Discuss the graphs in terms of transitions on the state diagram presented in Part (a). Demonstrate that your state machine correctly identifies the correct input pattern in the input string given.

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