Second generation software languages

Overview | Sample | Characteristics | Steps | Users
Development software

Overview

Early 1950's - Assembly Language

Mnemonic replaced binary with codes such as mov replacing a binary code.

Sample

HELLO.ASM ;"Hello,world" program in Borland's Turbo Assembler .MODEL small .STACK 100h .DATA HelloMessage DB 'Hello, world',13,10,'$' .CODE mov ax,@data mov ds,ax ;set DS to point to the data segment mov ah,9 ;DOS print string function mov dx,OFFSET HelloMessage ;point to "Hello, world" int 21h ;display "Hello, world" mov ah,4ch ;DOS terminate program function int 21h ;terminate the program END

Characteristics

Assembly Language
English-Like mnemonics
Machine Dependent
Easier to Use
Fast & efficient
Translated by an Assembler

Assembly language steps

Three stages in assembly programming

Enter Assembly code into a text file

Assembly code must be assembled (to produce an OBJect file, which is a binary equivalent of the text file). This is an intermediate stage allowing you to create small objects that can be combined with other objects to produce a useful program.
Then linked (to produce an EXEcutable file) - the Machine code

Ref [75]TurboAssembler'89

Users

What type of person would write in assembler ?

Programmer
Mathematician