🚀 go-pugleaf

In article <22690@shemp.CS.UCLA.EDU> wine@CS.UCLA.EDU () writes:
>We'd like to use our 5081 as a display device for images using Xwindows,
>but we can only get 16 levels of grey out of it.  Is there any way
>to get 256 levels of grey (hardware, and/or software)?  It's an awfully
>nice display, but we may have to get something else to do the job.
>
>--David Wine

   I have the same question here at the Astronomy Department at UC
Berkeley;  my experience (brief as it is) with the 5081 is that it
is just a (very large) PGA, since the PGA also has a palette of
256 out of 4096 colors and just 16 gray levers.  For the image processing
we do, we REALLY need 64 gray levels.  Any suggestions for possible
displays?

                Michael Richmond


--                                          Michael Richmond
"This is the heart that broke my finger."   richmond@astroplasma.berkeley.edu

In article <22773@agate.BERKELEY.EDU> richmond@astroplasma.berkeley.edu.UUCP 
(Michael Richmond) writes:
>In article <22690@shemp.CS.UCLA.EDU> wine@CS.UCLA.EDU () writes:
>>We'd like to use our 5081 as a display device for images using Xwindows,
>>but we can only get 16 levels of grey out of it.  Is there any way
>>to get 256 levels of grey (hardware, and/or software)?
>
>   I have the same question here at the Astronomy Department at UC
>Berkeley;


There is an official IBM "RPQ" for enhancements to the standard IBM 5081
Display. If I remember correctly, it will meet you requirements (no
promises). Please contact your local IBM marketing Representative. If that
doesn't work, write back to me.

	-- David

wine@maui.cs.ucla.edu writes:

> We'd like to use our 5081 as a display device for images using Xwindows,
> but we can only get 16 levels of grey out of it.  Is there any way
> to get 256 levels of grey (hardware, and/or software)? 

I had the same problem, but IBM-Denmark got hold of a new version of
the Color Palette chip for the Megapel Adapter cards. The new version
have a 3 x 8 bit entry (instead of 3 x 4) for each color to lookup,
giving 256 greylevels at your Megapel (and is faster?). As far as I
understand only X11 (AIX/RT X-Windows V2.1) running under AIX 2.2.1,
knows how to make use of all the 24 bits in the Color Palette.  I got
hold of some test programs (from IBM) which left no doubt that the
upgrade worked. I haven't yet tried it with X11, while I am waiting
(and waiting (and waiting...)) for NFS, before I will upgrade to
AIX2.2.1 and AIX/RT X-Windows V2.1.

Below a short description of the hardware upgrade, as I made it:

Prev : Bt451KG100 
       RAMDAC
       <serial no>

New  : Bt458KG125 
       RAMDAC
       <serial no>

Location: At the Megapel-controller card (the bottom one of the two
cards of the Megapel adapter) near the outlet for the RGB-signals,
grey, 3 cm square, (~ 1.25"). NOTE the writing at the chip is upside
down (if you have the RGB-outlet to your right).

Replace the chip and make sure the writing turns out upside down.
Note that it does *NOT* sit directly on the socket, there is a small
(~ 1 mm.) space of air between them.

Have fun, but be aware: the cards/chips are STATIC SENSITIVE DEVICES!
--
dearwolf@diku.dk                             Mikael C. Kjaerulff 
Department of Computer Science, University of Copenhagen, Denmark

Yes, there is an RPQ for the Megapel controller that will give you 
256 gray levels, or so I believe.  Talk to your sales person.


-- 
Nick Simicich --- uunet!bywater!scifi!njs --- njs@ibm.com (Internet)