Re: A89: dumb question


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Re: A89: dumb question




S43R80@aol.com wrote:
> 
> In a message dated 99-06-18 20:50:41 EDT, you write:
> 
> > Assuming, that 'whatever' happens to be on an even address, otherwise
> >  a surprise package with big red 'address error exception' stamped
> >  all over it will arrive in an instant ...
> >
> >  Zoltan
> >
> i don't think "clr.x" has anything to do with even/odd addresses at all...if
> i'm not mistaken i believe you are mistaken...
> i think but am not sure that the only time you have to worry about odd
> address is if you may be writing to one...then you will get that big red
> error you were refering to =)

no, he is right! first, clr do write to memory (how else would it clear it?) and
second, it applies to reads too..
all instuctions that work with w or l requiers even addresses..

but, if you just write one dc.b in your code, the assembler will automagically
align it.
BUT if you though write like this:

foo	dc.b  xx
whatev	dc.b  yy
bar	dc.b  zz

and tried to clr.w whatev, then you would get an address error...

//Olle


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