Assembly Language: Difference between revisions

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Assembly programs are much easier to understand than their corresponding machine code instruction streams, which are just numbers, but they are much more difficult to comprehend than, higher-level [[programming languages]] like, for example, [[PHP]].
Assembly programs are much easier to understand than their corresponding machine code instruction streams, which are just numbers, but they are much more difficult to comprehend than higher-level [[programming languages]], such as [[PHP]].


[[Category: CZ Live]]
[[Category: CZ Live]]
[[Category: Computers Workgroup]]
[[Category: Computers Workgroup]]

Revision as of 11:42, 30 March 2007

Assembly Language is a method of abstracting machine code instructions for a computer into commands recognizable by a human. Instead of dealing directly with bit sequences, programmers write programs in assembly by generating blocks of code using a small set of keywords (which are mapped to machine instructions by an assembler).

An example Hello World program written in pseudo-assembly for a MSDOS-based system is listed below. Original source: Assembly Language for the IBM-PC.


 .data
   hello_message db 'Hello, World!',0dh,0ah,'$'
 
 .code
 main proc
   mov ax,@data
   mov ds,ax
 
   mov ah,9
   mov dx,offset hello_message
   int 21h
 
   mov ax,4C00h
   int 21h
 main endp
 end main

Assembly programs are much easier to understand than their corresponding machine code instruction streams, which are just numbers, but they are much more difficult to comprehend than higher-level programming languages, such as PHP.