3 Address
Duration: 3 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- Discrete Mathematics: Permutation, Combination and Probability / क्रमचय, संचय एवं प्रायिकता, Set Theory, Relations, Functions, Propositional and Predicate Logic, Graph Theory, Group Theory
- Digital Logic: Digital Systems & Boolean Basics, Boolean Expression, Boolean Minimization, Logic Gates & Hardware, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep
- Computer Organization and Architecture: Basics of COA, Programming the Basic Computer, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design, Pipelining, Multiprocessors
- Programming: Language Design, C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++
- Data Structures: Introduction to DS, Array, Linked List, Stack, Queue, Tree, Graphs, Hashing
- Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
- Theory of Computation: Grammar, Regular Language Properties, Moore & Mealy Machines, Turing Machines
- 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, Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Pushdown Automata & CFG, Complexity Theory
- Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS, Security
- Database Management Systems: 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, ORDBMS, NoSQL
- Computer Networks: Introduction to CN, Data Communication, 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, Network Security
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This educational video provides a detailed lecture on 3-address instructions within computer architecture. The instructor defines the instruction format, consisting of an Opcode, two operands (Oprend1, Oprend2), and a Destination field. He explains that the Program Counter handles sequencing, removing the need for an address field in the instruction itself. The lecture uses the expression X = (A + B) * (C + D) to demonstrate translation into assembly language. Finally, he evaluates pros and cons, noting popularity due to binary nature but highlighting increased instruction length and space consumption compared to fewer-address formats.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a slide titled '3 Address Instruction' showing a table with headers: Opcode, Oprend1, Oprend2, and Destination. The instructor explains that the Program Counter manages sequencing, so the instruction doesn't need an address field. He notes that while programs are short in size, bits per instruction increase. He focuses on the example: 'in assembly language that evaluates X = (A + B) * (C + D)'. He breaks down the code: ADD R1, A, B for R1 <- M[A] + M[B], ADD R2, C, D for R2 <- M[C] + M[D], and MUL X, R1, R2 for M[X] <- R1 * R2. He underlines the equation and assembly lines to map them to the 3-address structure, specifically highlighting the Destination column for the final result.
2:00 – 3:08 02:00-03:08
The slide updates to show bullet points discussing advantages and disadvantages. The text states, 'It is relatively better than 4 address instruction.' The instructor elaborates that because most operations are binary, this format is 'very convenient with human understanding and that is why very popular.' He points to the disadvantage: 'Disadvantage is still it is very much lengthy, which uses a lot of space.' He gestures towards the assembly code example to illustrate the length, showing how a single mathematical expression requires multiple lines of code, each taking up space in memory, which is a trade-off for the ease of programming.
The lecture systematically builds understanding by first defining the technical structure of 3-address instructions and explaining the role of the Program Counter. It then grounds this theory with a concrete example of evaluating a mathematical expression, mapping each step to the instruction format. The lesson concludes with a critical evaluation, weighing the benefits of human readability and binary operation convenience against the drawback of increased memory usage due to longer instruction lengths, providing a comprehensive view of this architectural choice.

