GXLV Datasheet, PDF (153/247 Pages) National Semiconductor (TI) – Geode™ GXLV Processor Series Low Power Integrated x86 Solutions

Integrated Functions (Continued)
4.5.12 Palette Access Registers
These registers are used for accessing the internal palette
RAM and extensions. In addition to the standard 256
entries for 8-bpp color translation, the GXLV processor
palette has extensions for cursor colors and overscan
(border) color.
The Palette Access Register group consists of two 32-bit
registers located at GX_BASE+8370h and
GX_BASE+8374h. These registers are summarized in
Table 4-28 on page 141, and Table 4-33 gives their bit for-
mats.
Table 4-33. Display Controller Palette
Bit
Name
Description
GX_BASE+8370h-8373h
DC_PAL_ADDRESS Register (R/W)
Default Value = xxxxxxxxh
31:9
RSVD
Reserved: Set to 0.
8:0
PALETTE_ADDR Palette Address: The address to be used for the next access to the DC_PAL_DATA register. Each
access to the data register will automatically increment the palette address register. If non-sequen-
tial access is made to the palette, the address register must be loaded between each non-sequential
data block. The address ranges are as follows.
Address
0h - FFh
100h
101h
102h
103h
104h
105h - 1FFh
Color
Standard Palette Colors
Cursor Color 0
Cursor Color 1
Reserved
Reserved
Overscan (Color Border)
Not Valid
GX_BASE+8374h-8377h
DC_PAL_DATA Register (R/W)
Default Value = xxxxxxxxh
31:18
RSVD
Reserved: Set to 0.
17:0
PALETTE_DATA Palette Data: The read or write data for a palette access.
Note: When a read or write to the palette RAM occurs, the previous output value will be held for one additional DCLK period. This
effect should go unnoticed and will provide for sparkle-free update. Prior to a read or write to this register, the
DC_PAL_ADDRESS register should be loaded with the appropriate address. The address automatically increments after each
access to this register, so for sequential access, the address register need only be loaded once
Revision 1.1
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