Re: DHGR Video Riddle Solved!!!

[Phoenyx <quazar@dcnet2000.com>]

> If AN3 isn't user accessible, then how does one enable DHGR in software
> on a IIc? If you can't toggle AN3 in software, then the PAL will
> continue to force all graphics to be shifted out at 7MHz, i.e. no DHGR.
> So how exactlly does it work if AN3 isn't user accessible?

AFAIK, it is done in the hardware. I have researched some of this since
it didn't make sense. Dhires has always been a bit of a mystery to me
even with all the reading I have done on it. I have a basic understanding
of how the bitmaps work on the screen, just not at the hardware level.
IIRC, DHR mode is turned on by the soft switches in the $c000+ area I
forget the exact switches though.

I was also under the impression that your method of turning on the DHR
mode was not sanctioned by Apple Inc due to hardware issues. This may
also be why the capabilities of an extra screen mode was never mentioned.
It would not be compatible across the 8 bit systems.

-- 

Thank you for your time and interest. I hope it was helpful
or at least interesting.

Phoenyx,

Apple2 user since March 1984

Links to Phoenyx's pages:
preferred..... http://zip.to/Phoenyx_A2
alternate..... http://www.tinyangeldesigns.com/Apple2