256 Colors

["Bryan Parkoff" <nospam@nospam.com>]

    Why Apple Corp, Inc decide to limit 16 out of 256 colors each line?
Super NES can handle 256 colors each line.  Both of them use 65816 CPU.  Is
it because Apple Team are afraid that 256 colors might interfere I/O
softswitches in E1/C000?
    If Apple IIgs can be able to handle 256 colors at 320x200 resolution,
32,000 pixels can start at E0/2000 through E0/9D00 and another 32,000 pixels
can start at E1/2000 through E1/9D00.  It will be total $FA00 or 64,000
pixels.  It will look like real PC VGA 320x200x256.
    Why Apple IIgs choose only 4096 color possibility rather than 16,777,216
color possibility?  It looks like that 65816 can't overcome the limit of
16MB memory so Apple Team decided to use only 16x16x16 that equal to 4096
colors instead of 256x256x256 that equal to 16,777,216 colors.  It is very
strange.
    The same example is that Apple Team decided to provide only 6 or 8
colors on 280x192 resolution.  280x192 equals to 53,760 pixels.  6502 can't
handle 53,760 pixels because it can only limit 64KB so Apple Team did clever
by divide 53,760 pixels by 7 pixels that equals to 7,680 or $1E00.  It is
very close to total $2000 that is enough.
    You can see the difference why low resolution can only display 53,760
pixels in 16 colors because 28 or 56 pixels as one block can be each text
character.  It would be possible to implement 80x48 low resolution using 80
column like 40 column do, but it does not exist on any Apple II family.  I
do see that Apple IIgs do have 80x48 low resolution, but there must be a
special ROM routine that can be added to support 80x48 low resolution in 80
column.
    Please tell me what you think about the difference between Apple IIgs
and Super NES' 256 colors and 80x48 low resolution that Apple IIgs should
have (Does not exist.)


-- 
Bryan Parkoff