LM1253AN National Semiconductor, LM1253AN Datasheet - Page 48

• Manufacturer Part Number: LM1253AN
• Description: Monolithic Triple 180 MHz I2C CRT Pre-amp With Integrated Analog On Screen Display (OSD) Generator
• Manufacturer: National Semiconductor

www.national.com
Control Register Definitions
Bits 40–32:
Bits 49–41:
Bits 63–50:
ATTRIBUTE TABLES TO I
Button Box Formation
The value of the most significant Enhanced Feature Bit (EFB3) determines when to draw the left, right, bottom and top sides of
a Box. EFB1 denotes whether a box is raised or depressed, and EFB2 denotes whether the box is normal or ‘heavy’. For normal
boxes, the lowlight color is determined by the color code stored in the register EF2. For the heavy box feature, the lowlight is de-
termined by color code stored in register EF3.
Boxes are created by a ‘pixel override’ system that overwrites character cell pixel information with either the highlight color (EF1)
or low light shadow (EF2 or EF3) of the box. Only the top pixel line of the character and the right edge of the character can be
overwritten by the pixel override system.
To form a complete box, the left hand edge of a box is created by overwriting the pixels in the right most column of the preceding
character to the one being enclosed by the box.
The bottom edge of a box is created by either
1. overwriting the pixels in the top line of the character below the character being enclosed by the box.
Or:
Attribute Value
Color 3. These nine bits indicate the value of the color to be displayed as Color 3. This is displayed when the cor-
responding pixel data bit is 10b.
Color 4. These nine bits indicate the value of the color to be displayed as Color 4. This is displayed when the cor-
responding pixel data bit is 11b.
RESERVED.
0000b
0001b
0010b
0011b
0100b
0101b
0110b
0111b
1000b
1001b
1010b
1011b
1100b
1101b
1110b
1111b
2
1010b
1011b
1100b
1101b
1110b
1111b
C ADDRESS
Bits 21–18
TABLE 13. Attribute Tables To I
Depressed Box.
Blinking and Depressed Box.
Heavy Raised Box.
Blinking and Heavy Raised Box.
Heavy Depressed Box.
Blinking and Heavy Depressed Box.
(Continued)
Attribute Table
844Ch–844Fh
845Ch–845Fh
846Ch–846Fh
847Ch–847Fh
8448h–844Bh
8458h–845Bh
8468h–846Bh
8478h–847Bh
8440h–8443h
8444h–8447h
8450h–8453h
8454h–8457h
8460h–8463h
8464h–8467h
8470h–8473h
8474h–8477h
I
2
Two-Color
C Address
48
Description
2
C Address
Attribute Table
8500h–8507h
8508h–850Fh
8510h–8517h
8518h–851Fh
8520h–8527h
8528h–852Fh
8530h–8537h
8538h–853Fh
8540h–8547h
8548h–854Fh
8550h–8557h
8558h–855Fh
8560h–8567h
8568h–856Fh
8570h–8577h
8578h–857Fh
I
2
Four-Color
C Address