What is assembler, Computer Engineering

Assignment Help:

Q. What is Assembler?

An assembly program is used to transfer assembly language mnemonics to binary code for every instruction after the complete program has been written with support of an editor it's then assembled with help of an assembler. 

An assembler works in 2 stageswhich are: it reads your source code 2 times.  In first pass the assembler gathers all the symbols defined in the program accompanied by their offsets in symbol table.  On the 2ndpass through the source program it generates binary code for every instruction of the program and give all symbols an offset with respect to segment from symbol table.

The assembler produces three files. Object file, list file and cross reference file. The object file comprises the binary code for every instruction in program. It is created only when your program has been successfully assembled without errors.  Errors which are detected by assembler are known as the symbol errors.  For illustrationMOVE AX1, ZX1.

In the statement it reads the word MOVE and it attempts to match with mnemonic sets as there is no mnemonic with this spelling then it presumes it to be an identifier and searches for its entry in symbol table.  It doesn't even find it there hence gives an error as undeclared identifier.

List file is optional and comprises the source code, binary equivalent of every instruction and offsets of symbols in the program.  This file is for purelydocumentation purposes. A number of the assemblers available on PC are TURBO,MASM etc.


Related Discussions:- What is assembler

Micro programmed control and hardwired control, Explain micro programmed co...

Explain micro programmed control. Ans: A micro programmed control unit is made around storage till is called a control store where all the control signals are stored in a prog

Determine the simplified sop boolean expression, The Karnaugh map for a SOP...

The Karnaugh map for a SOP function is given below in figure. Determine the simplified SOP Boolean expression. Ans. F= B'C' + A'C'D + B'D'

What are the properties exposed by activex controls, An ActiveX control has...

An ActiveX control has four types of properties: 1. Stock:-> These are standard properties supplied to each control, such as font / color. The developer must activate stock pro

Multi-operating systems, The assignment enhances the acquisition of new kno...

The assignment enhances the acquisition of new knowledge through reading, research and practical work in class and at home. It requires critical thinking applied to real life tasks

Internal structure of agents - artificial intelligence, Internal Structure ...

Internal Structure of Agents: We have looked at agents in terms of their external influences and behaviors: they put in from the surroundings and perform rational actions to a

Analysis of website, In this part you are required to review and critique a...

In this part you are required to review and critique a website of a café or a restaurant of your choice. Your report should be a minimum 500 words with a maximum of 1000 words. You

List the properties which a hashing function should possess, List the prope...

List the properties which a hashing function should possess to ensure a good search performance. What approaches are adopted to handle collision? A hashing function h must poss

Explain about instruction cycle, Q. Explain about Instruction Cycle? Th...

Q. Explain about Instruction Cycle? The instruction cycle for this provided machine comprises four cycles. Presume a 2-bit instruction cycle code (ICC). The ICC can represent t

Maximum size of a database, What is the maximum size of a database that can...

What is the maximum size of a database that can be opened in Microsoft Access? Ans) 1 Gigabyte

Conjunctive normal form -artificial intelligence , Conjunctive Normal Form ...

Conjunctive Normal Form -artificial intelligence : For the resolution law to determine two sentences, they should both be in a normalized format known as conjunctive normal fo

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd