Fusion 878A
5.0 Control Register Definitions-Function 0
PCI Video Decoder
5.3 Local Registers (Memory Mapped)
100600B
Conexant
5-17
0x038—Chroma (V) Gain Register, Lower Byte (SAT_V_LO)
Upon reset SAT_V_LO is initialized to 0xB4. SAT_V_LO(0) is the LSB. SAT_V_MSB in the Miscellaneous
CONTROL register and SAT_V_LO concatenate to create a 9-bit register (SAT_V). Use this register to add a
gain adjustment to the V component of the video signal. You adjust the saturation by adjusting the U and V
color components of the video stream by the same amount. For normal saturation adjustment, the gain in both
the color difference paths must be the same (i.e. the ratio between the value in the U gain register and the value
in the V gain register should be kept constant at the default power-up ratio). When changing the saturation, if the
SAT_V_MSB bit is altered, take care to ensure that the other bits in the CONTROL register are not affected.
Table 5-4. SAT_V (SAT SAT_V_LO)
Bits
Type
Default
Name
Description
[7:0]
RW
0xB4
SAT_V_LO
This register is used to add a gain adjustment to the V component of
the video signal. You can adjust the saturation by adjusting the U
and V color components of the video stream by the same amount.
Decimal Value
Hex Value
Percent of Original
Signal
511
0x1FF
283.89 %
510
0x1FE
283.33 %
.
.
.
.
.
.
181
0x0B5
100.56 %
180
0x0B4
100.00 %
.
.
.
.
.
.
128
0x080
71.11 %
.
.
.
.
.
.
1
0x001
0.56 %
0
0x000
0.00 %