BT848 ETC, BT848 Datasheet - Page 112

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

C
SC Loop Control Register
SC Loop Control Register
Memory Mapped Location 0x040 – Even Field (E_SCLOOP)
Memory Mapped Location 0x0C0 – Odd Field (O_SCLOOP)
Upon reset it is initialized to 0x00. Reserved(0) is the least significant bit.
102
Bits
ONTROL
[4:3]
[2:0]
[7]
[6]
[5]
R
EGISTER
Type
RW
RW
RW
RW
RW
D
Default
0
0
0
00
00
EFINITIONS
Name
Reserved
PEAK
CAGC
CKILL
HFILT
HFILT
Reserved
Description
Reserved for future use. Must be written with a zero.
This bit determines if the normal luma low pass filters are imple-
mented via the HFILT bits or if the peaking filters are implemented.
This bit controls the Chroma AGC function. When enabled,
Chroma AGC will compensate for non-standard chroma levels.
The compensation is achieved by multiplying the incoming chroma
signal by a value in the range of 0.5 to 2.0.
This bit determines whether the low color detector and removal cir-
cuitry is enabled.
These bits control the configuration of the optional 6-tap Horizontal
Low-Pass Filter. The auto-format mode determines the appropriate
low-pass filter based on the horizontal scaling ratio selected. The
LDEC bit in the CONTROL register must be programmed to zero
to use these filters.
If the PEAK bit is set to logical one, the HFILT bits determine which
peaking filter is selected.
These bits must be set to zero.
0
1
0
1
0
1
00* = Auto Format. If auto format is selected when horizontally
01
10
11
01
10
11
L848A_A
= Normal luma low pass filtering
= Use luma peaking filters
= Chroma AGC Disabled
= Chroma AGC Enabled
= Low Color Detection and Removal Disabled
= Low Color Detection and Removal Enabled
= CIF
= QCIF
= ICON
= Minimum peaking
= Medium peaking
= Maximum peaking
scaling between full resolution and half resolution, no fil-
tering is selected. When scaling between one-half and
one-quarter resolution, the CIF filter is used. When scal-
ing between one-quarter and one-eighth resolution, the
QCIF filter is used, and at less than one-eight resolution,
the ICON filter is used.
Single-Chip Video Capture for PCI
Bt848/848A/849A
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