04-02-2013, 04:17 PM
Introduction to Assembly Language Programming
Introduction to Assembly.doc (Size: 46 KB / Downloads: 20)
Machine level language
Program is stored in successive memory locations by storing sequence of binary numbers corresponding to each instruction.
001010 11 000100
000000 00 000101
Drawbacks:
1. Programmer need to memorize thousands of instruction codes for CPU.
2. More error prone
Assembly level language
One level higher than machine language
Easier than machine level language.
Assembler translates AL programs into machine code which is stored in memory.
AL program statement format is:
Application Software
Designed to solve a specific problem (e.g. read email, browse the internet)
System Software
A set of tools designed to simplify programming for a specific machine (or hardware system)
Concerned with using hardware efficiently
Used to construct and run Application Software
Source Program
Human-readable program specification (e.g. C++, Assembly program)
Usually created using a text editor (ASCII file)
Object Program
Produced from a source program by compiling/assembling to “intermediate” machine code
“Intermediate” machine code augmented by:
• References (possibly undefined)
• Additional instructions related to combining the object program with other object programs, and/or executing the object program
Executable Program
Instruction sequence that a computer can directly execute (“machine code”)
• May be produced directly by a compiler/assembler
• Often produced by combining object programs