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DHGR Correction for KEGS32 & AppleWin



    I am working to capture video binary from Apple IIgs' motherboard which 
it has video graphic controller chip.  The VGC chip receives 4 bits for NTSC 
color from Mega II chip which it has 16 possible color.  Then 4 bits goes 
into 12 bits look-up out of 4,096 possible colors.  Only 16 12-bit string 
are chosen for DHGR color.
    Twelve bits come from VGC chip to the analog video port through three 
digital to analog converter chips.  It is what it is explained in Apple 
IIgs' Hardware Reference manual and the schematic.
    I intend to probe 12 bits as RGB signals and C sync signal to the VGC 
chip.  I use probes to see the oscilloscope screen.  I plan to buy logic 
analyzer sooner.  I predict to succeed if I capture 144 bits at this time to 
translate 12 RGB pixels.  It produces 4,096 possible DHGR data in one table 
which it uses 16 possible colors.  It is what I expect to use emulated NTSC 
on RGB when it has to be 100% identical to true Apple IIgs' analog RGB 
monitor into looking real SVGA monitor.
    If it has gone successful, would you be interested to depend on me to 
revise DHGR correction for your KEGS32 project, AppleWin project, and/or 
other emulator projects since I claim that all DHGR data are completely 
wrong for some decade?  HGR and LGR will be descended from DHGR table which 
it contains cut-off between even-odd and odd-even positions.  Please let me 
know.

Bryan Parkoff