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Old 19 September 2013, 22:24   #85
Amiga 500 User
Join Date: Jun 2013
Location: EU
Posts: 1,129
Originally Posted by Toni Wilen View Post
Silly scroller finally fixed.

This was really difficult to debug because it was not actual chipset emulation bug but internal emulation bug (internal buffer was not always cleared correctly, this is another speed optimization, only clear just enough, never too much) when resolution or number of bitplanes change mid-scanline. For some reason this didn't trigger with Disposable Hero or others that really abuse BPLCON0 mid-scanline.

This is one of those demos that have (most likely accidental) BPLCON0 write mid-scanline. I am quite sure coder was confused, he probably thought it was some HRM or chipset bug, then he decided to adjust bitplane pointers and/or DDFSTOP/STRT until display was fixed.
Just for info...
Have just tested it on a newer WinUAE b7(19.09.2013.) and found that there are still some blinking line appears (see pic.) on same place where before the white line was. Note: Its impossible to see it on a picture as not the whole line is blinking, only partially!

The main question is that now noticed the "Phenomena" logo it looks to be somehow shifted ... (forgot on this before) ...
Does this also happening on a real Amiga ?!

EDIT: Blinking line appears seams to be fixed in WinUAE b8 (21.09.2013.)!
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Last edited by amilo3438; 21 September 2013 at 15:31. Reason: Small corrections.
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