On Mon, 21 Apr 1997 10:21:47 +0200 
 ml@persius.rz.uni-potsdam.de (Michael Lorenz) wrote:

 > > topcat0 at intio0 addr 0x560000: 1280 x 1024 256 color hi-res catseye
 > >     display
 > 
 > just one question: what's the real difference between the catseye and
 > the topcat chip ?

The "topcat" is a 6-bit, non-accelerated color frame buffer.  The
"catseye" is either 8-bit color or 2-bit greyscale, and is accelerated.
If anyone has any different info about them, please speak up :-)

The reason they're both handled by the "topcat" driver is because they
are very similar ... the register layout is basically identical, with
the exception of additional accelerator registers on the catseye.  These
differences are dealt with only by the X server.

Unfortunately, this is about the limit of my knowledge of these beasts.
Documentation on them is hard to come by.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
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