Re: AppleColor 100 RGB monitor Questions

["Bryan Parkoff" <nospam@nospam.com>]

"Knut Roll-Lund" <kr-lund@nogarbage.online.no> wrote in message 
lNednc1on-Sv19XeRVnzvA@telenor.com">news:lNednc1on-Sv19XeRVnzvA@telenor.com...
> 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
Knut,

    You did a good effort, but I don't think that it looks correct.  I would 
like you to try another one please.

    You claim that $600B (24578) is to enable and disable color/monochrome. 
I don't think that it is correct.  All Apple II family only have one flag in 
one register inside $C05E.  $C05E is to turn on DHGR.  $C05F is to turn off 
DHGR.  RGB card has three flags in one register inside $C05E.
    Please try to use three procedures for yourself and also please tell 
Tempest about it.

    To follow three procedures below.  First, turn on Apple //e's power. 
Second, type, "PR#3" in Applesoft BASIC prompt.  Third, choose one of three 
procedures you want to follow.

1.    Turn on in $C05E  It will show funny colors like 4 colors in four 
vertical line in DHGR.

2.    Turn on in $C05E for first time.  Turn off in $C05F.  Then, turn on in 
$C05E second time.  It would give monochrome in DHGR.

3.    Turn on in $C05E for first time.  Turn off in $C05F for first time. 
Turn on $C05E for second time.  Turn off in $C05F for second time.  Turn on 
in $C05E for third time.  It would give you color in DHGR.

Bryan Parkoff