I didn't read very far before I found an error. You need to switch xpos and ypos around. Where you have ld de, (yPos). e = y pos, but d = clip mask. Simple little fix.

The topic seems to be in the right spot (ASM programming)

Or do you mean you wanted to post it as a reply to another topic?

Don't worry about it ^^

(On MaxCoderz forums, at first, the new topic button was called "Post" and the reply button was called "Reply". Many people got confused and started new topics as reply to other topics )

Just as an head up:

I feel that non-english posts made outside the dutch section of the forums (http://www.omnimaga.org/index.php?board=102.0 ) should include an english translation of them, especially help-related posts, so english users can understand, too (the help may be useful to others, too)

uit mijn hoofd doe zou ik dit doen:

Code: [Select]

ypos .equ AppBackUpScreen
xpos .equ AppBackUpScreen+1
clip_mask .equ AppBackUpScreen+2
    LD       A, 38
    LD      (xpos), A
    LD      A, 54                    ; Y position do display
    LD      (ypos), A
    LD      B, 9                      ; Length of Sprite in Y direction
    LD      D, (xpos)                   ;ik weet niet of D =ypos of E=ypos maar je kan het altijd nog omdraaien
    LD      E, (ypos)
    LD      IX, Sprite                           ; Label of sprite
    CALL   showsprite
ik weet dus niet of dit werkt maar in ieder geval moet het probleem wel duidelijk zijn nu...

Yay!
All I had to do was switch around xpos and ypos in the .equ part, didn't had to change anything else.
this is an example of something so small that I would never had found it without your help.

Oh, and doing
    LD      D, (xpos)                 
    LD      E, (ypos)
can't, since I just load Ypos into DE, not Xpos. (check the first post)

And I don't think its nessecary to do
ypos .equ AppBackUpScreen
xpos .equ AppBackUpScreen+1
clip_mask .equ AppBackUpScreen+2     ; Dont think the +2 is needed, because I justdo this:

ypos .equ AppBackUpScreen
xpos .equ ypos+1                           ;I just do the previous statement +1, that doesn't result in errors (I think), because
clip_mask .equ xpos+1                     ;I've even done +9 while the script wasnty working, and it still kept failing

Thanks alot!
This was one of the last hurdles to complete the programm, just 1 more thing to tacke but I'll ask (if needed only ofcource) that in another topic. (It's about permanently saving hi-scores/variables ect. in the archive in an APP)

Really, big thanks for all the help here.

In case you want a more technical explanation why you can't use bcalls that use data in the app, here it is.  The entire readable memory is divided into 4 sectors each 16KB in size.  There are many pages, but they have to swapped around and replace an existing page to be used in that sector.  Apps execute in the sector which is from $4000 to $7FFF as I'm sure you are aware.  It is write protected, but permits reading and executing.  The 1st sector is OS stuff and the last 2 are ram, programs, and the sp stack in normal circumstances.

Now here is where it gets interesting.  The operating system is much larger than just that one page, so when you make a call to something like _PutS or _DispImage the calculator has to swap in the page of the OS that has that routine in it.  And guess which sector it uses?  Its the one at $4000 where the app is.  That means your page is swapped out so the OS can call it's routine.  Now when it tries to read the data you passed to it, its just going to be some random junk on that page and not the actual data you intended since your page isn't at that location anymore!  That's why you either copy the data to ram or write your own routines to use it.