![200 Prog A
201 A=10
202 B=20
203 C=[201]+[202]
204 End
LOADER
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210 Prog A
211 A=10
212 B=20
213 c=[201]+[202]
214 End
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Secondary memory
Main memory](https://image.slidesharecdn.com/introduction-220722084156-2d37245a/85/Introduction-pptx-19-320.jpg)
Introduction.pptx
- 1. SOFTWARE Software is a set of instructions, data or programs used to operate computers and execute specific tasks. Software instructions tells a computer what to do.
- 3. SYSTEM SOFTWARE Operating System: manages all the resources such as memory, CPU, printer, hard disk, etc., and provides an interface to the user, which helps the user to interact with the computer system. Examples of operating systems are Linux, Apple macOS, Microsoft Windows, etc. Language Processor: converts programs written in high-level programming languages like Java, C, C++, Python, etc (known as source code), into sets of instructions that are easily readable by machines(known as object code or machine code). Device Driver: A device driver is a program or software that controls a device and helps that device to perform its functions. Every device like a printer, mouse, modem, etc. needs a driver to connect with the computer system eternally.
- 4. SYSTEM SOFTWARE System software is computer software designed • to operate and control the computer hardware • to provide a platform for running application software.
- 5. SYSTEM SOFTWARE System software consists of a variety of programs that support the operation of a computer • Assembler • Linker • Loader • Macro processor • Text editor • Debugger • File System • Database
- 6. SYSTEM SOFTWARE The role of Systems Software –interface between users, application software and hardware
- 7. APPLICATION SOFTWARE • Application software, also known as an application. • Application is computer software designed to help the user to perform specific tasks. • Examples include enterprise software, accounting software, and graphics software and media players.
- 8. Difference between System Software and Application Software System Software Application Software System software consists of a variety of programs that support the operation of a computer. for example operating system, assembler, loader, linker, and microprocessor and text editor. Application software is a set of one or more programs, designed to solve a specific problem. for example employee management system, bank management system, and media player. System software is system dependent application software is not a system dependent system software works directly with the hardware application software works directly with the system software. system software are written in machine or assembly languages. variety of programming languages can be used to write application software, such as C , Java and .NET
- 9. Types of System Software Compiler Assembler Linker Loader Macro processor Text editor Debugger File System Database
- 10. Compiler The compiler is software program that converts a program written in a high- level language (Source Language like C, C++, Java) to low-level language (Machine Language).
- 11. COMPILER TYPES Cross Compiler: that runs on a machine ‘A’ and produces a code for another machine ‘B’. It is capable of creating code for a platform other than the one on which the compiler is running. Source-to-source Compiler or transcompiler or transpiler: is a compiler that translates source code written in one programming language into the source code of another programming language.
- 12. COMPILER TYPES Incremental Compilers: is a compiler, which executes the recompilation of only a changed source instead of compiling the complete source code. Single-Pass Compiler: Single pass compiler reads the code only once and then translates it. The one-pass compiler passes only once through the parts of each compilation unit. Multi-Pass Compiler: A multi-pass compiler can process the source code of a program multiple times. • In the first pass, the compiler can read the source code, scan it, extract the tokens and save the result in an output file. • In the second pass, the compiler can read the output file produced by the first pass, produces machine code.
- 13. Assembler Assembly Level language Machine level language program program Assembler
- 14. Data Structures Pass 1 Pass 2 Intermediate file Object program Source program OPTAB SYMTAB LOCCTR • Operation Code Table (OPTAB) • Symbol Table (SYMTAB) • Location Counter (LOCCTR)
- 15. Load-and-Go Assembler • Load-and-go assembler generates their object code in memory for immediate execution. • No object program is written out, no loader is needed.
- 17. Linker Object File 1 Object File 2 Object File 3 Executable File
- 19. 200 Prog A 201 A=10 202 B=20 203 C=[201]+[202] 204 End LOADER 200 201 202 203 204 205 206 207 208 209 210 Prog A 211 A=10 212 B=20 213 c=[201]+[202] 214 End 215 Secondary memory Main memory
- 20. Reason for Program Relocation • To increase the efficiency of the machine • Want to load and run several programs at the same time (multiprogramming) • Must be able to load programs into memory wherever there is room • Actual starting address of the program is not known until load time
- 21. Processes to Run an Object Program • Loading – Brings object program into memory • Relocation – Modifies the object program where absolute addresses are specified • Linking – Combines two or more separate object programs and supplies information needed to allow cross- references. Absolute loader Loader Linking loader Linker
- 23. Macro processor Source Code (with macro) Expanded Source Code Macro processor
- 24. Macro Processor • Recognize macro definitions • Save the macro definition • Recognize macro calls • Expand macro calls Source Code (with macro) Macro Processor Expanded Code Compiler or Assembler obj
- 25. Copy code -- Example Source STRG MACRO STA DATA1 STB DATA2 STX DATA3 MEND . STRG . STRG . . Expanded source . . . STA DATA1 STB DATA2 STX DATA3 . STA DATA1 STB DATA2 STX DATA3 . { {
- 26. Text editor A text editor is a type of program used for editing plain text files. Editors or text editors are software programs that enable the user to create and edit text files. Windows: Notepad, WordPad UNIX OS: vi, emacs, Jed, Pico
- 27. Text editor Types of Editors Line editor: you can only edit one line at a time or an integral number of lines. Ex : Teleprinter, edlin, teco Stream editors: the file is treated as continuous flow or sequence of characters instead of line numbers, which means here you can type paragraphs. Ex : Sed editor in UNIX Screen editors: the user is able to see the cursor on the screen and can make a copy, cut, paste operation easily. It is very easy to use mouse pointer. Ex : vi, emacs, Notepad Word Processor: it allows one to use some format to insert images, files, videos, use font, size, style features. Structure Editor: Structure editor focuses on programming languages. It provides features to write and edit source code. Ex : Turbo C, Netbeans IDE
- 28. Debugger A debugger or debugging tool is a computer program that is used to test and debug other programs. • Break points • Watch window
- 29. Previous Year Questions 5. The language which a computer can understand is a. high level language b. assembly language c. machine language d. all of the above
- 30. Previous Year Questions 5. The language which a computer can understand is a. high level language b. assembly language c. machine language d. all of the above
- 31. Previous Year Questions 11. A linker a. is a software programme b. combines part of a programme c. is a programme used to load monitor into main memory d. Both (a) and (b)
- 32. Previous Year Questions 11. A linker a. is a software programme b. combines part of a programme c. is a programme used to load monitor into main memory d. Both (a) and (b)
- 33. Previous Year Questions 15. An assembler in a computer system prepares a. machine-language programme from a symbolic language programme b. object programme c. assembles computer instructions and data in the machine d. None of these
- 34. Previous Year Questions 15. An assembler in a computer system prepares a. machine-language programme from a symbolic language programme b. object programme c. assembles computer instructions and data in the machine d. None of these
- 35. Previous Year Questions 20. Which one of the following is not system software a. MS DOS b. UNIX C. Windows d. JAVA
- 36. Previous Year Questions 20. Which one of the following is not system software a. MS DOS b. UNIX C. Windows d. JAVA
- 37. Previous Year Questions 67 An 'Assembler' for microprocessor is used for a. assembly of processors in a production line b. creation of new programs using different modules c. translation of a program from assembly language to machine language d. Translation of a higher-level language into English text.
- 38. Previous Year Questions 67 An 'Assembler' for microprocessor is used for a. assembly of processors in a production line b. creation of new programs using different modules c. translation of a program from assembly language to machine language d. Translation of a higher-level language into English text.