[Coco] RGB2VGA on DE0-Nano (improvements)

Matthew Stock stock at bexkat.com
Sat Aug 30 08:40:21 EDT 2014


Mark,

Thanks for the idea...  I already put together a simple VGA w/framebuffer
configuration recently on a DE1 to teach myself how such things worked.  At
the moment, the framebuffer memory is updated by SPI (non-Coco), but
interfacing to the Coco bus and figuring out how to pull the video memory
from the bus as it passes by could be interesting.  I haven't studied that
part of the Coco before.

Long weekend project!
  -Matt



On Sat, Aug 30, 2014 at 8:07 AM, Mark McDougall <msmcdoug at iinet.net.au>
wrote:

> On 30/08/2014 8:33 PM, Gene Heskett wrote:
>
>  any sampling is likely something that would need
>> addressed not by grabbing the RGB output of a software GIME chip or a
>> 6847, but by grabbing the data straight from memory as it is delivered to
>> those chips and generating the VGA completely external to any emulation of
>> the coco's color generating chips.
>>
>
> Which is exactly how the Carte Blanche (Apple II) and MISE (TRS-80 Model
> I) do the job. Much easier, much cleaner, and more flexible.
>
> Then you have the F18A for the TI99/4A, an FPGA-based drop-in solution
> that is commercially available for the TI99/4A, which is what Gene goes on
> to dream about! ;)
>
> <http://codehackcreate.com/archives/30>
>
> So... not outside the realm of possibility for the Coco!
>
> Regards,
>
> --
> |              Mark McDougall                | "Electrical Engineers do it
> |  <http://members.iinet.net.au/~msmcdoug>   |   with less resistance!"
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
>


More information about the Coco mailing list