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Learning applications for the study of sequential digital devices

The application is a computer learning tool designed as an additional teaching aid used in the study section "sequential logic devices" course "Fundamentals of digital technology."

The application is designed for the purpose of studying and classifying digital devices of sequential type, the principles of their functioning, conventional graphic symbols, truth tables, input and output signals, as well as the research work of sequential units in static mode. It may be useful to teachers of technical universities, students of the digital circuitry, as well as for those who want to self learn the basics of digital electronics.

The app covers the main types of sequential devices. These include a variety of trigger elements, registers and counters of various modifications. A distinctive feature of all these devices is the availability of memory, which allows storage of the current state. This allows the use of such devices for short-term storage of individual bits of information small amounts of code words, the implementation of these simple changes, such as the shift to the right or to the left increments or decrements. A total of 42 devices are considered, most of which (30) make up the triggers. Among them, synchronous, asynchronous, single-stage and two-stage RS, D, T and JK flip-flops with direct and inverse inputs, with static and dynamic control. In addition, treated and parallel shift registers, summing, subtracting and reversible counters and frequency dividers.

The basis of the application programming model - emulator. Emulation allows the algorithm to demonstrate the functioning of the device selected with the help of interactive interface elements, which include indicators of input and output signals.

The output signals of sequential device depend not only on the state in which the device is located, but also from a plurality of signals at its inputs. In turn, any changes to the input signal enough to touch the screen.

Touching any of the inputs of the device entails a change of input signal values ​​to the opposite: a logic zero is replaced by a unit and vice versa. Displays the values ​​of logical variables at the input and output device is performed color LEDs: blue color of the indicator corresponds to a logical 0, red - a logical 1, and gray - a high impedance state output.

In addition to the simulation work in the annex for each of the devices under consideration are brief theoretical information, including basic definitions, pin assignment and description of the functioning of the algorithm, as well as the truth table describing the operation of the device in a formalized manner.

The application is a logical continuation of my previous research: "Combination devices" and "Designer PDNF schemes."