LM1276 National Semiconductor Corporation, LM1276 Datasheet - Page 34

• Manufacturer Part Number: LM1276
• Description: 150 Mhz I2c Compatible Rgb Preamplifier With Internal 512 Character Osd Rom, 512 Character Ram And 4 Dacs
• Manufacturer: National Semiconductor Corporation

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Bit 5
Bit 6
Bit 7
Bits 6–0
Bit 7
Bits 7–0
Control Register Definitions
Vertical Blank Duration Register:
OSD Character Height Register:
Enhanced Feature Register 1:
X
Enhanced Feature Register 2:
X
Enhanced Feature Register 3:
X
Bits 8–0
Bits 15–9
Bits 8–0
Bits 15–9
Bits 8–0
Bits 15–9
X
X
X
Reserved. This bit should be set to zero.
Reserved. This bit should be set to zero.
Setting this bit will cause a software reset. All registers (except this one) are loaded with their default values. All
operations currently in progress are aborted (except for I
the reset has been completed.
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.
Reserved. This bit should be set to zero.
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).
CHSDWCTRLB1 (0x840A)
X
X
X
BBHLCTRLB1 (0x8406)
BBLLCTRLB1 (0x8408)
Reserved
Reserved
Reserved
These determine the button box highlight color.
Reserved. These bits should be set to zero.
These determine the button box lowlight color.
Reserved. These bits should be set to zero.
These registers determine the heavy button box lowlight, shading or shadow color.
Reserved. These bits should be set to zero.
Reserved
X
X
X
RSV
X
X
X
X
X
X
(Continued)
X
X
X
CHARHTCTRL (0x8404)
VBLANKDUR (0x8403)
Vertical Blanking Duration
Highlight - Green
Lowlight - Green
Shadow - Green
CH[7:0]
34
G[2:0]
G[2:0]
G[2:0]
VB[6:0]
2
C transactions). This bit automatically clears itself when
Heavy Button Box Lowlight/Shading/Shadow
CHSDWCTRLB0 (0x8409)
BBHLCTRLB0 (0x8405)
Highlight - Red
BBLLCTRLB0 (0x8407)
Lowlight - Red
Shadow - Red
R[2:0]
R[2:0]
R[2:0]
Button Box Highlight Color
Button Box Lowlight Color
Highlight - Blue
Lowlight - Blue
Shadow - Blue
B[2:0]
B[2:0]
B[2:0]