![]() ![]() For example, if the state is S0 and input is 0, then the next state is S0 and output 0. This is a Moore model sequential circuit, since the output is 1 when the circuit is in state S3 and is 0 otherwise.Īfter getting the state diagram, determining the characteristic table will be now an easy work, since we know the present state, input, output and the next state. In this way, the circuit stays in S3 as long as there are three or more consecutive 1’s received. Any 0 input sends the circuit back to S0. If more 1’s are detected, the circuit stays in S3. The third consecutive 1 sends the circuit to state S3. If the next input is 1, the change is to state S2 to indicate the arrival of two consecutive 1’s, but if the input is 0, the state goes back to S0. If the input is 0, the circuit stays in S0, but if the input is 1, it goes to state S1 to indicate that a 1 was detected. It is derived by starting with state S0, the reset state. The state diagram for this type of circuit is shown in the figure. ![]() Suppose we wish to design a circuit that detects a sequence of three or more consecutive 1’s in a string of bits coming through an input line (i.e., the input is a serial bit stream). Let’s take a Moore Model and design the sequence detector. First we have to determine what model we will use, MEALY or MOORE. So let’s draw the state diagram, which is the preliminary step for the implementation of any sequential circuit. The circuit detects the presence of three or more consecutive 1’s in a string of bits coming through an input line. Important :This tutorial is best seen using firefox web browser and may not look well on Internet Explorer.Today, we will see how to design a sequential circuit using a very basic example, sequence detection. ![]() Currently this website is getting more than 1 million hits every month.Ī special thanks to Paolo Franchetti for fixing grammar and spelling mistakes in Verilog tutorial. All the examples have been simulated using Icarus Verilog simulator. Of course, new learners will always find this tutorial useful. ![]() I hope some day this Verilog tutorial becomes a reference for all the engineers out there. If you have been a frequent visitor, you should have noticed how these tutorial pages have improved. Every time I update my web page, I make sure I add something new in the Verilog tutorial section. This Verilog tutorial was started a long time ago. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
January 2023
Categories |