ALXD800EEXJ2VD AMD (ADVANCED MICRO DEVICES), ALXD800EEXJ2VD Datasheet - Page 377

• Manufacturer Part Number: ALXD800EEXJ2VD
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of ALXD800EEXJ2VD

• Operating Temperature (min): 0C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

Display Controller Register Descriptions
6.6.21.1 Attribute Controller Index/Data
Index Address
Data Address
Type
Reset Value
The attribute controller registers do not have a separate address for writing index and data information. Instead, an internal
flip-flop alternates between index and data registers. Reading Input Status Register 1 (3BAh or 3DAh) clears the flip-flop to
the index state. The first write to 3C0h following a read from Input Status Register 1 will update the index register. The next
write will update the selected data register. The next write specifies a new index, etc.
6.6.21.2 EGA Palette
Index
Type
Reset Value
AMD Geode™ LX Processors Data Book
Bit
7:6
4:0
Bit
7:6
5:0
5
Name
RSVD
INT_PAL_AD
DATA_RG_INX
Name
RSVD
COL_VAL
3C0h
3C1h (R)
3C0h (W)
R/W
xxh
00h-0Fh
R/W
xxh
Attribute Controller Index Register Bit Descriptions
Description
Reserved.
Internal Palette Address. This bit determines whether the EGA palette is addressed by
the video pixel stream (bit = 1) or by the Attribute Controller Index register (bit = 0). This
bit should be set to 1 for normal VGA operation. CPU I/O accesses to the palette are dis-
abled unless this bit is a 0.
Data Register Index. This field addresses the individual palette and data registers.
Description
Reserved.
Color Value. Each of these 16 registers is used to expand the pixel value from the frame
buffer (one, two, or four bits wide) into a 6-bit color value that is sent the video DAC. The
EGA palette is “programmed out of the way” in 256 color mode. These registers can only
be read or written when the Internal Palette Address bit in the Index register (3C0h) is 0.
EGA Palette Register Bit Descriptions
33234C
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