Re: How does the apple2 RGB card work?

["Bryan Parkoff" <none@nospam.net>]

"mdj" <mdj.mdj@gmail.com> wrote in message 
1148958883.622674.204310@38g2000cwa.googlegroups.com">news:1148958883.622674.204310@38g2000cwa.googlegroups.com...
>
> Bryan Parkoff wrote:
>
>>     I am not sure what I understand that you are referring $2000-$3FFF in
>> aux memory for HGR (not DHGR).  Can you please explain little more?
>
> This is the undocumented Mode 5 I referred to previously ...
> Essentially it applies the same technique used to produce 40 column
> colour text to the HIRES display. The main memory buffer is treated as
> monochrome HIRES, and the auxiliary buffer is used for colour
> information.
>
> It would seem that the VIDEO7 crew after implementing mono DHR, then
> colour DHR as seperate modes, realised that MIX was only an extra IC
> away. The other modes are also very simply generated from the available
> data stream.
>
> There was an article on the undocumented mode in Apple Assembly Line,
> which is how I learned of it's existence. The AppleColour RGB demo disk
> also includes a demonstration for it, but it's use other than emulating
> monochrome HIRES correctly is pretty limited, IMHO
>
> It's worth preserving even just to achieve that, however.
>
> Matt
>
Matt,

    Where can I find monochrome HGR undocumented article on website?

Bryan Parkoff