Thread: Need some help from someone who knows assembly

  1. #1
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    Need some help from someone who knows assembly

    Can't find an assembly board....someone here must be familiar with it

    Real easy question. Have a project were I need to use auto incrementation and non auto incrementation.

    Is auto incrementation
    Code:
    LDAA 1,x+                 ;load to acc A the value of x and increment the address of x
    STAA 1,y+                 ;store acc A to the address of y and increment y
    SUBB #1                       ;subtract 1 from the total number of mem trans.
    bne  loop
    and manual incrementation

    Code:
    LDAA 	0,x                      	;load to accumulator A the value of x
    inx                           		;increment the address of x
    STAA 	0,y                      	;store accumulator A to the current y address
    iny                           		;increment the address of y
    SUBB 	#1                       	;subtract 1 from the total number of mem trans.
    bne  	loop
    thanks

  2. #2
    C++ Witch laserlight's Avatar
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    Moved to Tech board.

    So, what is your question?
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

  3. #3
    Kernel hacker
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    It does look about right, but of course, with you not saying WHICH assembler you are doing this for, and me not recognizing the target processor.

    In PDP-11 you would do:
    Code:
    $1:
        mov   (r0)+, r3
        mov   r3, (r1)+
        dec    r2
        bne   $1
    Code:
    $1:
        mov   (r0), r3
        inc     r0
        mov   r3, (r1)
        inc     r1
        dec    r2
        bne   $1

    In 68K it would be:
    Code:
    $1:
        move  (a0)+, d0
        move  d0, (a1)+
        dec     d1
        bne    $1
    and
    Code:
    $1:
        move  (a0), d0
        addq   #1, a0
        move  d0, (a1)
        addq   #1, a1
        dec     d1
        bne    $1

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  4. #4
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    so basically using the + is auto incrementation? and using inx, iny is not? I've run them both with the HCS12, they both work.

  5. #5
    Kernel hacker
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    Quote Originally Posted by thestrapman View Post
    so basically using the + is auto incrementation? and using inx, iny is not? I've run them both with the HCS12, they both work.
    Ok, so WHAT is your question - you obviously have the syntax correct (or your testing isn't very thorough) if you get the right result and both versions of code works.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

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