Path: chuka.playstation.co.uk!cipher-ltd.demon.co.uk!tim
From: Tim Hammonds <tim@cipher-ltd.demon.co.uk>
Newsgroups: scee.yaroze.problems.pc
Subject: Backgrounds (BG) in interlaced mode
Date: Thu, 11 Mar 1999 23:14:53 +0000
Organization: PlayStation Net Yaroze (SCEE)
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I have just started to dabble with my Yaroze and am trying out some of
its features.

The manuals seem to infer that you can use BG functions in interlaced
mode: Page 142 of the Library Reference manual (GsInitFixBg16) makes
reference to NTSC interlaced mode vertical screen resolutions.

When I try to use GsSortFixBg16 in PAL mode with PAL interlace mode at
640x512 resolution, I get screen flicker. Further investigation shows
that the every other line (odd numbered lines - I think) of my BG data
is getting transmitted to the frame buffer, but not the rest, hence the
flicker. 

NB. The simple test that demonstrates this is to only register the BG in
the odd numbered OT (1). When the BG is only registered in the even
numbered OT (0) none of the BG is displayed and the screen is rock
solid.

Any ideas?

Tim.