Message board for the users of flat assembler.
> Windows > bin to string convertion
Hello: this is not a question, i know the binary to decimal conversion is
a well-known subject but i have made my own version of the function
and i want to show it so others can use it or improve it.
it uses the MagicNumber and a few shifts and sub's:
the buffer is like: bufer db 'xxxxxxxxxx',0
the zero is needed
the buffer is filled with the string (no leading zeros)
the function has a rep movsb that moves the characters to the begining
of the buffer even if the buffer is full so maybe you want to insert a
cmp ecx,11 to skip moving the characters to where they allready are.
i use the following sintax:
X is the number to divide by 10
R is the integer result
r is the residue (or modulo,i don't now the exact word in english)
so for instance if X=4152 then R=415 and r=2
;EAX number to convert ;ESI pointer to a 10-bytes-long,zero terminated buffer bin2str: push ecx push edi mov ecx,1 ;ecx is the counter mov edi,esi add esi,10 ;-------div10 .divide: push eax mov edx,3435973837 ;MagicNumber mul edx pop eax ;eax = X and dl,$f8 ;edx = 8R sub eax,edx ;eax = X-8R shr edx,2 ;edx = 2R sub eax,edx ;eax=X-8R-2R = X-(8R+2R) = X-10R = r shr edx,1 ;edx=R xchg eax,edx ;now eax=R and edx=r ;-write char:-------dl=(0-9) or dl,$30 ;dl=('0'-'9') dec esi mov [esi],dl inc cl cmp eax,0 je .exit jmp .divide ;------------------- .exit: cld rep movsb pop edi pop ecx ret ;EAX = 0 ;ESI = one byte ahead of the zero in the zero-terminated-string
|02 Aug 2006, 03:49||
< Last Thread | Next Thread >
Copyright © 1999-2020, Tomasz Grysztar. Also on GitHub, YouTube, Twitter.
Website powered by rwasa.