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Atari coding BBS
| jsr (a0) from within vbl |
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Posted by: Per Almered (XiA)
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Jul,23.2009-18:51
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Me again with another "why doesn't this work?" question... 8-)
I'd like to be able to call different subroutines at the end of the VBL to make it easy to have precalcing stuff going on in the background, so I figured this would be a good idea:
[normal code]
lea blankextra,a0
move.l a0,extraroutine
vbl: ; hooked at $70
[...all sorts of stuff]
move.l extraroutine,a0
jsr (a0)
rts
blankextra
rts
extraroutine dc.l 0
...and then I could just switch in different routines by placing their addresses at the address of the "extraroutine" label.
In "regular code" this works fine, but not from within the vbl, which might be because it's an exception thing (but I *DO* have an RTS at the end of the vbl, not an RTE!)
Is there a good solution to this problem? Apart from making lots of different VBL routines?
Thanks in advance,
Per.
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Topic
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Posted by
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Date
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jsr (a0) from within vbl
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Per Almered (XiA)
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Jul,23.2009-18:51
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Re: jsr (a0) from within vbl
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PeP
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Jul,23.2009-19:28
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Re: jsr (a0) from within vbl
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Per Almered (XiA)
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Jul,23.2009-21:38
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Re: jsr (a0) from within vbl
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PeP
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Jul,24.2009-01:46
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Re: jsr (a0) from within vbl
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Per Almered/XiA
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Jul,24.2009-06:39
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Re: jsr (a0) from within vbl
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mikro
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Jul,24.2009-08:40
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Re: jsr (a0) from within vbl
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mikro
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Jul,24.2009-08:44
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Re: jsr (a0) from within vbl
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Per Almered (XiA)
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Jul,24.2009-09:26
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Re: jsr (a0) from within vbl
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mikro
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Jul,24.2009-10:35
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Re: jsr (a0) from within vbl
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PeP
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Jul,24.2009-15:40
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Re: jsr (a0) from within vbl
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Per Almered (XiA)
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Jul,24.2009-22:13
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What's the anti-troll code?
That's your personal code to be able to add comments and messages on the dhs.nu site.
Don't have a code or forgot it? Fix it here.
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