PORTIBM PC Portable (uses same BIOS as XT) 03C6-03C9 - EGAEnhanced Graphics Adapter(Enhanced Graphics Adapter) IBMInternational Busiuness Machines's second color video board for the IBMInternational Busiuness Machines PCIBM PC family, capable of a maximum resolution of 640x350 pixels in 16 simultaneous colors of a total of 64 possible colors./VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers./MCGAMulti-Color Graphics Array(Multi-Color Graphics Array) The low-end color adapter offered in IBMInternational Busiuness Machines's early PS/2IBM PS/2, any model series machines. - DAC(Digital-to-Analog Converter) A hardware device (in its simplest form, nothing more than a set of interconnected resistors) which converts a digital number into an analog signal whose voltage is proportional to the value of the digital number.  VGAVideo Graphics Array and later color video boards use DACs to convert color values into the analog signals sent to the display; sound boards normally use DACs as well. REGISTERS
Range:	PORTIBM PC Portable (uses same BIOS as XT) 03C6h or PORTIBM PC Portable (uses same BIOS as XT) 02C6h (alternate)
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 03C0h,PORTIBM PC Portable (uses same BIOS as XT) 03C2h,PORTIBM PC Portable (uses same BIOS as XT) 03C4h,PORTIBM PC Portable (uses same BIOS as XT) 03CAh,PORTIBM PC Portable (uses same BIOS as XT) 03CEh"EGAEnhanced Graphics Adapter(Enhanced Graphics Adapter) IBMInternational Busiuness Machines's second color video board for the IBMInternational Busiuness Machines PCIBM PC family, capable of a maximum resolution of 640x350 pixels in 16 simultaneous colors of a total of 64 possible colors.",PORTIBM PC Portable (uses same BIOS as XT) 03D0h
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 83C6h"Wingine"

03C6  RW  (VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers., MCGAMulti-Color Graphics Array(Multi-Color Graphics Array) The low-end color adapter offered in IBMInternational Busiuness Machines's early PS/2IBM PS/2, any model series machines.) PEL mask register (default FFh)
		 VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.:	AND mask for color-register address.
		 MCGAMulti-Color Graphics Array(Multi-Color Graphics Array) The low-end color adapter offered in IBMInternational Busiuness Machines's early PS/2IBM PS/2, any model series machines.:	Never change from the default FFh.
03C6  RW  HiColor ET4000 (Sierra RAMDACs e.g. SC11486, SC11481, SC11488):
		 Enable HiColor feature: beside other assignments,
		 consequtive read 3C6h 4 times and write magic value 80h to it.
03C7  -W  (VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.,MCGAMulti-Color Graphics Array(Multi-Color Graphics Array) The low-end color adapter offered in IBMInternational Busiuness Machines's early PS/2IBM PS/2, any model series machines.,CEG-VGA) PEL address register (read mode)
		 Sets DAC(Digital-to-Analog Converter) A hardware device (in its simplest form, nothing more than a set of interconnected resistors) which converts a digital number into an analog signal whose voltage is proportional to the value of the digital number.  VGAVideo Graphics Array and later color video boards use DACs to convert color values into the analog signals sent to the display; sound boards normally use DACs as well. in read mode and assign start of color register
		 index (0..255) for following read accesses to 3C9h.
		 Don't write to 3C9h while in read mode. Next access to
		 03C8h will stop pending mode immediatly.
03C7  -W  (CEG-Color VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers. w/ Edsun Labs RAMDACs)
		 Enable and set Countinous Edge Graphics Mode:
		 Consecutive writely the following three key sequences in read
		 mode (!) to 3C9h register DEh : 'CEG', 'EDS', 'UNx' (x see
		 below). Current CEG mode can be read from palette register
		 BFh 'blue', write access to that register will disable CEG
		 features.
		 In CEG modes by combining old with new colors and dynamically
		 changing palette values, the effective colors displayable
		 are enhanced dramatically (in EDP modes up to virtually 32bit
		 truecolor) on standard 16/256 color VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.. Also, effective
		 resolution enhancement takes effect by anti-aliasing.
		 Necessary EDP escape sequences should be moved to image
		 border or single colored areas, if possible.

		 REP-mode: if pixel are doubled in current video mode
		 EDP-mode: pseudo-truecolor with Edsun dynamic palette
		 (see #P0698,#P0699)

		 Palette-color-register single-byte-format (each 3 times):
		  Mode A:		  Mode C:
		   bit7-4: mix code	   bit3	 : 0=color, 1=code
		   bit3-0: color code	   bit2-0: color / mix code
		  Mode B:		  Mode D:
		   bit7-5: mix code	   bit7-0: see mix code table
		   bit4	 : 0=new, 1=old	  Non-CEG modes:
		   bit3-0: color code	   bit7-0: as usual

		 In EDP modes, video-memory-palette-changing escape-sequences:
		  Mode A:     Mode B:	  Mode C:     Mode D:
		   7/escape    7/escape	   7/escape    0BFh
		   red	       red	   red7-4      red
		   green       green	   red3-0      green
		   blue	       blue	   green7-4    blue
		   address     address	   green3-0    address
					   blue7-4
					   blue3-0
					   address
03C7  R-  VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.	DAC(Digital-to-Analog Converter) A hardware device (in its simplest form, nothing more than a set of interconnected resistors) which converts a digital number into an analog signal whose voltage is proportional to the value of the digital number.  VGAVideo Graphics Array and later color video boards use DACs to convert color values into the analog signals sent to the display; sound boards normally use DACs as well. state register
		bit7-2 reserved
		bit1-0: 00b write palette cycle (write mode)
			01h reserved
			10b reserved
			11b read palette cycle (read mode)
03C8  RW  (VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.,MCGAMulti-Color Graphics Array(Multi-Color Graphics Array) The low-end color adapter offered in IBMInternational Busiuness Machines's early PS/2IBM PS/2, any model series machines.) PEL address register (write mode)
		 Sets DAC(Digital-to-Analog Converter) A hardware device (in its simplest form, nothing more than a set of interconnected resistors) which converts a digital number into an analog signal whose voltage is proportional to the value of the digital number.  VGAVideo Graphics Array and later color video boards use DACs to convert color values into the analog signals sent to the display; sound boards normally use DACs as well. in write mode and assign start of color register
		 index (0..255) for following write accesses to 3C9h.
		 Don't read from 3C9h while in write mode. Next access to
		 03C8h will stop pending mode immediatly.
03C8  RW  (Genoa SuperEGA) SuperEGA control register (all emulation modes)
		  bit7-2: reserved
		  bit1	: 0=EGAEnhanced Graphics Adapter(Enhanced Graphics Adapter) IBMInternational Busiuness Machines's second color video board for the IBMInternational Busiuness Machines PCIBM PC family, capable of a maximum resolution of 640x350 pixels in 16 simultaneous colors of a total of 64 possible colors. mode, 1=backward compatibility mode
		  bit0	: not used
03C8  R?  (S3 Trio32/64) General Input Port (see #P0738)
03C9  RW  (VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.,MCGAMulti-Color Graphics Array(Multi-Color Graphics Array) The low-end color adapter offered in IBMInternational Busiuness Machines's early PS/2IBM PS/2, any model series machines.) PEL data register
		 Three consequtive reads (in read mode) or writes (in write
		 mode) in the order: red, green, blue. The internal DAC(Digital-to-Analog Converter) A hardware device (in its simplest form, nothing more than a set of interconnected resistors) which converts a digital number into an analog signal whose voltage is proportional to the value of the digital number.  VGAVideo Graphics Array and later color video boards use DACs to convert color values into the analog signals sent to the display; sound boards normally use DACs as well. index
		 is incremented each 3rd access.
		  bit7-6: HiColor VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers. DACs only: color-value bit7-6
		  bit5-0:			 color-value bit5-0


(Table P0698)
Values for EDSUN CEG (Continuous Edge Graphics) modes::
 x:  mode:	 colors:  mix:	pixel depth:  effective colors:
 0 = disabled	   256	   -	     8		    256
 1 = A		    16	  16	     8		   1920
 2 = A+REP	    16	  16	  8 dblscn	   1920
 3 = A+EDP	    15	  16			truecolor
 4 = reserved	     -	   -	     -		     -
 5 = B		    16	   8	     8		    960
 6 = B+REP	    16	   8	  8 dblscn	    960
 7 = B+EDP	    15	   8			truecolor
 8 = reserved	     -	   -	     -		     -
 9 = C		     8	   8	     4		    224
 10 = C+REP	     8	   8	  4 dblscn	    224
 11 = C+EDP	     7	   8			truecolor
 12 = reserved	     -	   -	     -		     -
 13 = D		   223	  32	     8		 792096
 14 = D+REP	   223	  32	  8 dblscn	 792096
 15 = D+EDP	   223	  32			truecolor
SeeAlso: #P0699


(Table P0699)
Values for EDSUN CEG mixing codes:
 Mode A:	       |  Mode C:
 mix: new:	old:   |   mix: new:   old:   colorcode:
   0 = 32/32	0/32   |    0 =	  -	 -     0
   1 = 30/32	2/32   |    1 =	  -	 -     1
   2 = 28/32	4/32   |    2 =	  -	 -     2
   3 = 26/32	6/32   |    3 =	  -	 -     3
   4 = 24/32	8/32   |    4 =	  -	 -     4
   5 = 22/32   10/32   |    5 =	  -	 -     5
   6 = 20/32   12/32   |    6 =	  -	 -     6
   7 = 18/32   14/32   |    7 =	  -	 -     7/EDP
   8 = 16/32   16/32   |    8 = 30/32	2/32   -
   9 = 14/32   18/32   |    9 = 28/32	4/32   -
  10 = 12/32   20/32   |   10 = 26/32	6/32   -
  11 = 10/32   22/32   |   11 = 24/32	8/32   -
  12 =	8/32   24/32   |   12 = 22/32  10/32   -
  13 =	6/32   26/32   |   13 = 20/32  12/32   -
  14 =	4/32   28/32   |   14 = 18/32  14/32   -
  15 =	2/32   30/32   |   15 = 16/32  16/32   -
---Mode B:	       |  Mode D:
 mix: new:	old:   |   mix:	      new:   old:  description:
   0 = 30/32	2/32   |   00h..BEh =	-      -   normal color
   1 = 26/32	6/32   |   BFh	    =	-      -   EDP
   2 = 22/32   10/32   |   C0h	    = 32/32   0/32
   3 = 18/32   14/32   |   C1h	    = 31/32   1/32
   4 = 14/32   18/32   |   C2h	    = 30/32   2/32
   5 = 10/32   22/32   |   ...	    =  ...    ...
   6 =	6/32   26/32   |   DFh	    =  0/32  32/32
   7 =	2/32   30/32   |   E0h-FFh  =	-      -   normal color
SeeAlso: #P0698