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inhahe



Joined: 18 Jul 2008
Posts: 2
Location: miami.fl.usa
inhahe
How do I declare variables that have a place in memory but don't take up any bytes in the output file? I mean it seems a shame to use up extra bytes in the file for variables that don't need an initial value. (I'm kinda new to assembly.)
Post 18 Jul 2008, 02:56
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comrade



Joined: 16 Jun 2003
Posts: 1137
Location: Russian Federation
comrade
See http://flatassembler.net/docs.php?article=manual#1.2.2

Basically, use either the "db ?" syntax, or the "rb" syntax.
Post 18 Jul 2008, 03:20
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LocoDelAssembly
Your code has a bug


Joined: 06 May 2005
Posts: 4633
Location: Argentina
LocoDelAssembly
Just by defining them with the value "?" (for example: aByte db ?).

Note however that the uninitialized variables must be placed AFTER any initialized data or instructions, otherwise the "?"'s will be filled with zeroes (and will take up space).

Example:
Code:
org $100
jmp exit
aByte db ?
exit: int $20    
Makes a 5 bytes file while
Code:
org $100
jmp exit
exit: int $20
aByte db ?    
Makes a 4 bytes file.
Post 18 Jul 2008, 03:23
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