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Old 22 October 2019, 15:25   #19
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Join Date: Dec 2014
Location: germany
Posts: 229
Originally Posted by ross View Post
EDIT: now that comes to mind, and if I remember correctly, there is a demo that does it to make an effect with the copper!
(only a little change to x value to shift initial copper position)
But to not lost sync every other line reset the position.

I quote myself :
[ Show youtube player ]

Fast forward to 11:45.
The copper effect on the upper part.
Very interesting, thanks for the link! So copper position is compared against VHPOS, which can be changed? Didn't know that this is possible!

Are DMA and horizontal display sync also affected? So if I change horiz. position to 0 in the middle of the line, will the hardware start a new DMA cycle (refresh, audio..)? And if I set it to $0D, will it restart with audio DMA only?
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