Cp Offset Block - Analog Devices ADV7610 Hardware User's Manual

Hardware User Guide
ALT_DATA_SAT, IO, Address 0x02[0]
A control to disable the data saturator that limits the output range independently of OP_656_RANGE. This bit is used to support
extended data range modes.
Function
ALT_DATA_SAT
0 (default)
1

CP OFFSET BLOCK

The offset block consists of three independent adders, one for each channel. Using the A_OFFSET, B_OFFSET, and C_OFFSET registers,
a fixed offset value can be added to the data. The actual offset used can come from two different sources:
The ADV7610 includes an automatic selection of the offset value, dependent on the CSC mode that is programmed by the user. The
RGB_OUT and OP_656_RANGE
A manual, user defined value can be programmed.
When the offset registers (A_OFFSET, B_OFFSET, and C_OFFSET) contain the value 0x3FF (reset default), the offset used is determined
using the automatic selection process. For any other value in the offset registers, the automatic selection is disabled and the user-
programmed offset value is applied directly to the video. Refer to the flowchart in Figure 36.
USE VALUE FROM I
OFFSET_A/B/C[9:0] DIRECTLY
CHANNEL
For RGB type output data, the three offset values should be programmed to 0 or 64 (desired code output for black video). For YPbPr type
output data, A_OFFSET[9:0] should be set to 64 (desired code for black); B_OFFSET[9:0] and C_OFFSET[9:0] (for Pr and Pb) are
typically set to 512 (midrange).
Notes
•
Adding an excessive offset onto the data will result in clipping of the signal.
•
The offset value can only be positive; it is an unsigned number.
•
ADV7610 employs sequencers for the offset values that prohibit intermediate wrong values to be applied.
•
The I 2 C sequencer treats the three offset values as separate entities. To update all three offset values, a single sweep of I
the CP map, Register 0x77, Register 0x78, Register 0x79, and Register 0x7A is sufficient.
Description
Data saturator enabled or disabled according to OP_656_RANGE setting
Reverses OP_656_RANGE decision to enable or disable the data saturator
bits are used to derive offset values.
NO
2
I C REGISTER VALUE
OFFSET_A/B/C[9:0] ==
2 C REGISTER
RGB_OUT = 1
OP_656_RANGE = 1
A 64dec
B
64dec
C 64dec
Figure 36. Channel A, Channel B, and Channel C Automatic Value Selection
0x3FF
OFFSET
OP_656_RANGE = 0 OP_656_RANGE = 1
0dec 64dec
0dec 512dec
0dec 512dec
Rev. 0 | Page 109 of 184
YES
RGB_OUT = 0
OP_656_RANGE = 0
0dec
512dec
512dec
UG-438
2 C writes to