Re: DHGR Video Riddle Solved!!!

["Arkain" <rwking@no.usa.spam.net>]

Almost completely true with 2 small exceptions. The IIc *does* have
annunicators. If it didn't, you wouldn't be able to do DHGR graphics on it
at all!

DHGR graphics do seem to be a 28 bit block. It seems that the only bit that
changes the graphics from color to B&W is bit 7 from the 1st aux byte in
each 4 byte column. If it's on then you get B&W dots(phase shifted of
course) otherwise you get color blocks.

APEX was probably limited in text width due to that it used the 140 color
blocks instead of the 560 B&W dots. Since it takes a horizontal minimum of 6
character dots + 1 space dot to display reasonably clear text...

Arkain

Phoenyx <quazar@dcnet2000.com> wrote in message
39BC49F0.9AE5B753@dcnet2000.com">news:39BC49F0.9AE5B753@dcnet2000.com...
> I think you will find this because the DHR memory is supposed to be
> accessed in a 28 bit fashion IE 4 bytes. These bits are then used by
> the hardware to display color sequences. There was more info on this
> related to the Apex system which included support for DHR and even used
> some GS fonts for text. Sadly, the text width was limited to about 20
> columns or so. Many of the Apex functions use this 28 bit method, even
> the SCRN routine which required a little manipulation to get the exact
> bit required. As mentioned, the DHR on my file://c is better than the GS'
> output. This surprised me since the author used a GS for developing it.
> Perhaps he used a composite monitor. Apex also offered a method to put
> the system into a 'mono' mode. This also didn't work on my file://c but
does
> work on my GS. This allows that it is possible to toggle the mono bit
> but I don't know how this was done.
>
> As for the 'other' DHR mode. It may be pointless since it will only be
> available on the IIe. The GS, as mentioned won't support it and the
file://c
> won't either because it has no user accessible annunciators.
>
> --
>
> 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