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Re: AppleColor 100 RGB monitor Questions

Tempest wrote:


I have a quick question about the AppleColor 100 RGB monitor (the IIe
RGB monitor, not the IIgs one).  The monitor works great, everything
looks nice and clear (no color smearing or fringy edges).  However the
monitor has some issues on certain programs, mostly games.  Some games
like Airheart play in monochrome, while other games like Prince of
Persia and Kings Bounty have some graphical distortion (the text on the
title screen looks blurry for example). These aren't the normal
Composite to RGB differences you see like when playing IIe games on a
IIgs monitor, these are some serious video issues.

Has anyone else had these problems? Is there a way to fix them?  I
think someone once told me that it could be that some bit isn't being
set properly by the game and the monitor is going into monochrome mode
accidentally or that it was the mixed graphics/text mode that was
causing the problem (mode 3 I believe).  If this is the case, would
using a different interface card fix the problem?  I'm currently using
the one that came with the monitor (the official one), but I think
there are at least two other cards I can use with it.
I have a solution for the black and white problem, a poke that works for some games, it just did for Manic Mansion. 

I start up the IIe and press ctrl-reset to get basic prompt
and write
POKE24587,1
then insert the Manic Mansion boot disk and write
PR#6
to boot the disk
Unfortunately the text is then less readable but I think this is like the IIgs RGB. It would have been so much better if the game had handled this, text in 0 mode and graphics in 1 mode.
Obviously this is a register that holds this state and it is then applied every time graphics is written so that the state is inherited by the graphics written (per byte?) and stored somewhere so that the displaying circuit can distinguish between bitmap (text) and color graphics.
I found this by examining the RGB demo FLASCARDS basic program and there I found this poke was done and a REM that said '0=bitmap 1=color pixels'. It seems this status is set to 0 on cold start. Changing it to 1 before warm starting the game seems to work. The game is not aware of this poke and does nothing to change it... 

Knut