On 24/06/18 15:19, Gareth's Downstairs Computer wrote:
> Presumably there is a video buffer somewhere which
> will display any pixels that you choose to put there,
> without there being any activity from the GPU part of the
> video controller?
>

Er...I suspect strongly that is NOT the case.

Not at hardware level.

the whole thrust of GPUs is to put a complex bit of bit blatting between
the CPU and the screen memory that you can't bypass.


> How is its area, frame rate and X and Y pixel range determined?
>
> Also, for dynamic video such as DVB there must be some means of
> instructing the graphics processor how to overwrite that area?
>
That sounds more like my (limited) understanding of GPUs.

sling 'em a high level command, and let them take the strain.


> Has there been published any disassembly of the graphics library
> to work out what is going on so that 64 bitters could drive it
> from A64?
>

I would think you can find the source easily enough.


> Yours etc,
> Confused from Tunbridge Wells
>
>


--
  “A leader is best When people barely know he exists. Of a good leader,
who talks little,When his work is done, his aim fulfilled,They will say,
“We did this ourselves.”

― Lao Tzu, Tao Te Ching

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