VIDC20 Data Sheet
The registers values are dependant upon the size of the LCD screen to be driven, and are calculated in the following way:
Off-15 = (3xL + 8) mod 15 Off-9 =(7xL+4)mod9 Off _S = (1xL + 3) mod 5 Off 2 =0
Where L is the number of lines in the upper panel of the dual panel LCD screen.
Bits 7-1 of register 0 are only used in test mode, and must all be set to zero in normal operation. msel[2:0] are test bits and should be programmed low.
4.1.4 Border Colour Register. Address 4H
This register defines the physical border colour, and is programmed with a 28 bit word. Note that this register is programmed directly, independent of the value of the video palette address pointer.
31 30 29 26 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 6 3 2 1 0 0 1 0 0 E E E E 8 B B B B 8 B BIG G G G G G G G R R R RR R R RI
Ext	Blue	Graen	Red Physical Colour	Physical Colour	Physical Colour	Physical Colour
4.1.5 Cursor Palette: Addresses 5H-7H
These three registers are programmed with the physicalcolour of the three logicalcursor colours. Note that cursor logical colour 00 is defined as being transparent (i.e. no cursor display), and this location is used for the Border Colour Register above.
31 30 29 28 27 26 25 26 23 22 21 20 19 18 17 16 15 16 13 12 11 10 9 6 7 6 5 4 3 2 1 0
0	1	x	x	E	E	E	E TB B	B	B	B B	B BIG G G G G G G GR R R R	R R	R RI
~ Fxt	Blue	Green	Red
Logical Colour -'	Physiwl Colour	Physical Colour	Physical Colour	Physical Colour
4.1.6 Horizontal Cycle Register (HCR): Address SOH
This register defines the period, in pixels, of the horizontal scan. i.e. display time + retrace time.
This is a 14 bit register of which the bottom 2 bits must be programmed to 0. If N pixels are required in the horizontal scan period, then value (N-8) should be programmed into the HCR. (N must be a multiple of 4).
31 30 29 28 27 26 25 26 23 22 21 20 19 18 17 16 15 16 13 12 11 10 9 8 7. 6 5 4 3 2 1 0 FIT 0	0	0	0	0	0	x	x	x	z	z	x	z	x	x	x	x	x	0	OI
NCR value
18