Date   : Mon, 02 Mar 2009 13:45:43 +0100
From   : kortink@... (John Kortink)
Subject: Fwd: New Screen Modes with ARM7 Co-Processor?

On Mon, 2 Mar 2009 12:36:44 +0000 (GMT), tommowalker@...
wrote:

>
>> I know the difference. I think we are talking at cross
>> purposes here.
>> 
>> The object of the exercise is to double the vertical
>> resolution of existing modes. Not to halve the horizontal
>> resolution in the process.
>> 
>> Hence 'interlace sync + video' mode could do the trick,
>> but would require 40K linearly addressable memory. Which
>> brings me back to my earlier message.
>
>Why does it need to be linearly addressable?

Because the CRTC needs it to be. Why is that so hard to
understand ?

If it is in 'interlace sync + video' mode, and it needs
to display our 'double vertical resolution' modes, i.e.
640 x 512 x 2 colour, 320 x 512 x 4 colour, or 160 x 512
x 16 colour modes, it will need 40K linearly addressable
memory.


John Kortink

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