Character Font Access Register:

CHARFONTACC (0x8402)

Reserved

Select

Plane

X

XXXXX

ATTR

FONT4

Bit 0

This is the Color Bit Plane Selector. This bit must be set to 0 to read or write a two-color attribute from the range

0x0000 to 0x2FFF. When reading or writing four-color attributes from the range 0x3000 to 0x3FFF, this bit is set to

0 for the least significant plane and to 1 for the most significant plane. It is also required to set this bit to read the

individual bit planes of the four color character fonts in 0x3000 to 0x3FFF and 0x7000 to 0x7FFF.

Bit 1

This is the Character/Attribute Selector. This applies to reads from the Display Page RAM (address range

0x8000–0x81FF). When a 0, the character code is returned and when a 1, the attribute code is returned.

Bits 7–2

Reserved. These should be set to zero.

Vertical Blank Duration Register:

VBLANKDUR (0x8403)

Res’d

Vertical Blanking Duration

X

VB[6:0]

Bits 6–0

This register determines the duration of the vertical blanking signal in scan lines. When vertical blanking is enabled,

it is recommended that this register be set to a number greater than 0x0A.

Bit 7

Reserved. This bit should be set to zero.

OSD Character Height Register:

CHARHTCTRL (0x8404)

CH[7:0]

Bits 7–0

This register determines the OSD character height as described in the section Constant Character Height

Mechanism. The values of this register is equal to the approximate number of OSD height compensated lines

required on the screen, divided by 4. This value is not exact due to the approximation used in scaling the character.

Example: If approximately 384 OSD lines are required on the screen (regardless of the number of scan lines) then

the Character Height Control Register is programmed with 81 (0x51).

Enhanced Feature Register 1:

Button Box Highlight Color

BBHLCTRLB1 (0x8406)

BBHLCTRLB0 (0x8405)

Reserved

Highlight - Green

Highlight - Red

Highlight - Blue

XXXXXXX

G[2:0]

R[2:0]

B[2:0]

Bits 8–0

These determine the button box highlight color.

Bits 15–9

Reserved. These bits should be set to zero.

Enhanced Feature Register 2:

Button Box Lowlight Color

BBLLCTRLB1 (0x8408)

BBLLCTRLB0 (0x8407)

Reserved

Lowlight - Green

Lowlight - Red

Lowlight - Blue

XXXXXXX

G[2:0]

R[2:0]

B[2:0]

Bits 8–0

These determine the button box lowlight color.

Bits 15–9

Reserved. These bits should be set to zero.

Enhanced Feature Register 3:

Heavy Button Box Lowlight/Shading/Shadow

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