China
Africa
Explore chapters and articles related to this topic
Synchronous Sequential Circuits
Published in Sajjan G. Shiva, Introduction to Logic Design, 2018
A sequential circuit can be described completely by a state table that is very similar to the ones shown for flip-flops in Figures 6.4 through 6.9. For a circuit with n flip-flops, there will be 2n rows in the state table. If there are m inputs to the circuit, there will be 2m columns in the state table. At the intersection of each row and column, the next-state and the output information are recorded. A state diagram is a graphical representation of the state table, in which each state is represented by a circle and the state transitions are represented by arrows between the circles. The input combination that brings about the transition and the corresponding output information are shown on the arrow. Analyzing a sequential circuit thus corresponds to generating the state table and the state diagram for the circuit. The state table or state diagram can be used to determine the output sequence generated by the circuit for a given input sequence if the initial state is known. It is important to note that for proper operation, a sequential circuit must be in its initial state before the inputs to it can be applied. Usually the power-up circuits are used to initialize the circuit to the appropriate state when the power is turned on. The following examples will illustrate the analysis procedure.
Digital Electronics
Published in Walter Fox Smith, Experimental Physics, 2020
A state diagram is a graphical picture of the operation of a synchronous system that is somewhat similar to the flow charts often used to describe computer programs. In this, we draw each of the states of the system in a little bubble and then we draw arrows between states showing the transitions that are possible. We label the bubbles with the names of the states and we label the arrows with the conditions that cause the transitions to be taken.
Modelling and Simulation of Construction Cyber-Physical Systems
Published in Salah Wesam Alaloul, Cyber-Physical Systems in the Construction Sector, 2022
Syed Saad, Wesam Salah Alaloul, Kumeel Rasheed, Syed Ammad
State Charts or State Diagrams are used to provide an abstract representation of a system’s actions. This action is examined and described by a sequence of events that may occur in one or more states. There are several different types of state diagrams, each with its own semantics. Each diagram normally depicts a single class of objects and tracks the various states of those objects as they move through the scheme. One of the earliest examples of a state diagram was introduced by Charles Babbage in 1871. Babbage was interested in designing an automatic loom for use by handloom weavers, and to this end, he proposed a system of wires and sliders, which cams would control. Each wire or slider had a different function; to control the machine, one had to identify the location of each part at any given time. To do this with minimal effort, Babbage developed an “analytical expression” (now called a state diagram) that showed all possible states at once rather than individually as they were changed from one event to another. A state diagram may be used to model computer hardware or software systems such as microprocessors, digital logic circuits or applications programs, respectively. State diagrams are also used in modelling biological processes such as gene expression levels under various conditions. State diagrams are typically not suitable for modelling mechanical objects like automobiles because these objects have a finite sets of states but can change between these states very quickly while retaining their physical integrity at every instant during the transition process, this kind of behaviour is best modelled using other tools like Petri nets and flowcharts instead (which both allow feedback loops). The most popular form of state diagram is called the UML Activity Diagram because it is frequently used with UML class diagrams. The unified modelling language also includes two more forms: sequence diagrams and collaboration diagrams which both share some common features with activity diagrams.
From state diagrams to sequence diagrams: a requirements acquisition approach
Published in International Journal of Computers and Applications, 2019
Bingyang Wei, Harry S. Delugach, Yi Wang
A state diagram consists of states connected by transitions. The occurrence of an event might fire a transition that causes the object to exit the current state and enter a new state. When a transition fires, an effect attached to the transition is performed. State diagram is aimed at capturing all admissible sequences of state transitions. The rest of Section 2.1 introduces the concepts in graph theory that we will be using in Section 3.