Priority Encoder

Duration: 4 min

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Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Theory of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory
  10. Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  11. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
  12. Computer Networks: Introduction to CN, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware Basics, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture introduces the Priority Encoder, a digital circuit designed to handle situations where multiple inputs are active simultaneously, a condition that renders standard encoders ineffective. The instructor explains that a priority encoder incorporates a priority function, ensuring that if two or more inputs are high, the input with the highest priority takes precedence. He illustrates this concept by drawing a block diagram with n inputs and binary outputs, emphasizing the need for a circuit that can resolve conflicts between active signals. The text on the screen explicitly states, "In some practical cases more than one input can be high at a time, there we can not use simple encoder." He further clarifies that the operation is such that "the input having the highest priority will take precedence." In the second segment, the instructor details the operation of a 4-to-2 priority encoder using a comprehensive truth table. He establishes the priority order as I3 > I2 > I1 > I0. He systematically fills the truth table, assigning 'd' (don't care) to lower-priority inputs when a higher-priority input is active. For instance, if I3 is 1, the outputs correspond to binary 3, regardless of other inputs. He then derives the Boolean expressions for the outputs O1 and O0 based on the populated truth table, writing O0 = I3 + I3'I2'I1 and O1 = I3 + I3'I2 on the board. This process demonstrates how to simplify logic for priority-based encoding. The instructor points to specific rows in the table to justify the 'd' values, showing that lower inputs are irrelevant when a higher one is asserted. He specifically writes the equation for O0 first, noting that it is high when I3 is high or when I3 and I2 are low but I1 is high. Similarly, O1 is high when I3 is high or when I3 is low and I2 is high. This detailed derivation provides a clear method for designing priority encoder logic circuits. The table shows rows for inputs 0001, 001d, 01dd, and 1ddd, mapping to outputs 00, 01, 10, and 11 respectively.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the concept of a Priority Encoder, explaining that simple encoders fail when multiple inputs are high simultaneously. He draws a block diagram with n inputs and binary outputs to visualize the circuit. The on-screen text highlights that in practical cases, more than one input can be high, necessitating a circuit with a priority function where the highest priority input takes precedence.

  2. 2:00 – 4:16 02:00-04:16

    The instructor constructs a truth table for a 4-to-2 priority encoder with inputs I3, I2, I1, I0 and outputs O1, O0. He fills the table based on the priority order I3 > I2 > I1 > I0, using 'd' for don't care conditions. He derives the Boolean expressions O0 = I3 + I3'I2'I1 and O1 = I3 + I3'I2, pointing to specific rows to justify the logic and don't care assignments.

The video progresses from defining the problem of multiple active inputs to the solution of a priority encoder, and finally to the implementation via a truth table and Boolean equations. The instructor systematically builds the logic, showing how higher priority inputs override lower ones, which is essential for understanding digital system design where signal conflicts must be resolved deterministically.

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