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Groups > comp.sys.apple2.programmer > #1924

Re: DA statement not registering after running compiled program.

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jamesiwalker77 wrote:
> It seems to me that the DA statement is somehow not registering.
> 
> My code is:
>      ORG     $300
>      LDA     $6000
>      STA     $2000
> DONE RTS
>      ORG     $6000
>      DA      $FFFF
> 
> I compiled this program, and Merlin shows correct compilation, with the
> values of memory addresses $6000 and $6001 both set to $FF.
> 
> However, after I save the source and object code (after compiling), I
> leave
> the assembler, switch to HGR and BRUN the program.  There should be a
> white
> line in the upper left corner of the screen.  There are pixels plotted
> there, but not a white line.  It seems to be pulling other values from
> $6000 and $6001 than what my DA statement should put in those addresses. 
> Even after going to the monitor and examining $6000 and $6001, neither are
> $FF.
> 
> Anyone have any idea what is going on here?  It seems that there's
> possibly
> some point about how program memory is saved which I am missing here.
>
Below is an amended source code w/o having to deal with two separate object
code that should also work.
And yes, the Merlin assembler works as designed and is a great tool.
	ORG	$0300
	LDX	#DATEND-DATBEG-1
]LOOP	LDA	DATBEG,X
	STA	$6000,X
	DEX
	BPL	]LOOP
* Now you can  play as if data was @ $6000
	LDA	$6000
	STA	$2000
DONE	RTS
DATBEG	ORG	$6000
	DA	$FFFF
* The following ORG restore the original assembly PC (adjusted by the amount
* of code assembled since the ORG $6000 directive above).
	ORG
DATEND


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growing up is optional..
But the other way round is as true.

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Thread

DA statement not registering after running compiled program. jamesiwalker77@gmail.com - 2015-10-25 21:59 -0700
  Re: DA statement not registering after running compiled program. John Brooks <jbrooks@blueshiftinc.com> - 2015-10-25 22:55 -0700
  Re: DA statement not registering after running compiled program. Benoit0123 <bgilon@free.fr> - 2015-10-26 10:08 +0000
  Re: DA statement not registering after running compiled program. "Anton Treuenfels" <teamtempest@yahoo.com> - 2015-10-26 08:49 -0500
  Re: DA statement not registering after running compiled program. jamesiwalker77@gmail.com - 2015-10-26 10:23 -0700

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