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Integrated Functions (
Continued
)
G
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+8374h. These registers are summarized in
Table 4-28 on page 141, and Table 4-33 gives their bit for-
mats.
GX_BASE+8370h
and
Table 4-33. Display Controller Palette
Bit
Name
Description
GX_BASE+8370h-8373h
DC_PAL_ADDRESS Register (R/W)
Default Value = xxxxxxxxh
31:9
8:0
RSVD
Reserved:
Set to 0.
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
Color
0h - FFh
Standard Palette Colors
100h
Cursor Color 0
101h
Cursor Color 1
102h
Reserved
103h
Reserved
104h
Overscan (Color Border)
105h - 1FFh
Not Valid
PALETTE_ADDR
GX_BASE+8374h-8377h
DC_PAL_DATA Register (R/W)
Default Value = xxxxxxxxh
31:18
17:0
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
RSVD
Reserved:
Set to 0.
Palette Data:
The read or write data for a palette access.
PALETTE_DATA