Geode GXLV Processor Series Low Power Integrated x86 Solutions

Integrated Functions (Continued)4.5.12 Palette Access RegistersThese registers are used for accessing the internal paletteRAM and extensions. In addition to the standard 256entries for 8-bpp color translation, the GXLV processorpalette has extensions for cursor colors and overscan(border) color.Bit Name DescriptionTable 4-33. Display Controller PaletteThe Palette Access Register group consists of two 32-bitregisters located at GX_BASE+8370h andGX_BASE+8374h. These registers are summarized inTable 4-28 on page 141, and Table 4-33 gives their bit formats.GX_BASE+8370h-8373h DC_PAL_ADDRESS Register (R/W) Default Value = xxxxxxxxh31:9 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. Eachaccess to the data register will automatically increment the palette address register. If non-sequentialaccess is made to the palette, the address register must be loaded between each non-sequentialdata block. The address ranges are as follows.AddressColor0h - FFhStandard Palette Colors100h Cursor Color 0101h Cursor Color 1102hReserved103hReserved104hOverscan (Color Border)105h - 1FFh Not ValidGX_BASE+8374h-8377h DC_PAL_DATA Register (R/W) Default Value = xxxxxxxxh31:18 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. Thiseffect should go unnoticed and will provide for sparkle-free update. Prior to a read or write to this register, theDC_PAL_ADDRESS register should be loaded with the appropriate address. The address automatically increments after eachaccess to this register, so for sequential access, the address register need only be loaded onceGeode GXLV Processor SeriesRevision 1.3 153 www.national.com