BT848 ETC, BT848 Datasheet - Page 106

• Manufacturer Part Number: BT848
• Description: Single-Chip Video Capture for PCI
• Manufacturer: ETC

C
Brightness Control Register
Brightness Control Register
Memory Mapped Location 0x028 – (BRIGHT)
Upon reset it is initialized to 0x00.
96
Bits
ONTROL
[7:0]
R
EGISTER
Type
RW
D
Default
0x00
EFINITIONS
BRIGHT
Name
BRIGHT
Hex Value
0x80
0x81
.
.
0xFF
0x00*
0x01
.
.
0x7E
0x7F
Description
The brightness control involves the addition of a two’s complement
number to the luma channel. Brightness can be adjusted in 255
steps, from –128 to +127. The resolution of brightness change is
one LSB (0.39% with respect to the full luma range).
L848A_A
Binary Value
1000 0000
1000 0001
.
.
1111 1111
0000 0000*
0000 0001
.
.
0111 1110
0111 1111
Single-Chip Video Capture for PCI
Brightness Changed By
Number
of LSBs
–128
–127
.
.
–01
00
+01
.
.
+126
+127
Bt848/848A/849A
Percent of
Full Scale
–50%
–49.6%
–0.39%
0%
+0.39%
+49.2%
+49.6%
Brooktree
®