saf7118 NXP Semiconductors, saf7118 Datasheet - Page 61

• Manufacturer Part Number: saf7118
• Description: Multistandard Video Decoder With Adaptive Comb Filter And Component Video Input
• Manufacturer: NXP Semiconductors

Philips Semiconductors
SAF7118_3
Product data sheet
8.5 VBI data decoder and capture (subaddresses 40h to 7Fh)
The SAF7118 contains a versatile VBI data decoder.
The implementation and programming model is in accordance with the VBI data slicer
built into the multimedia video data acquisition circuit SAA5284.
The circuitry recovers the actual clock phase during the clock run-in period, slices the data
bits with the selected data rate, and groups them into bytes. The result is buffered into a
dedicated VBI data FIFO with a capacity of 2
frequency, signal source, field frequency and accepted error count must be defined in
subaddress 40h.
The supported VBI data standards are shown in
For lines 2 to 24 of a field, per VBI line, 1 of 16 standards can be selected (LCR24_[7:0] to
LCR2_[7:0] in 57h[7:0] to 41h[7:0]: 23
The definition for line 24 is valid for the rest of the corresponding field, normally no text
data (video data) should be selected there (LCR24_[7:0] = FFh) to stop the activity of the
VBI data slicer during active video.
To adjust the slicers processing to the input signal source, there are offsets in the
horizontal and vertical direction available: parameters HOFF[10:0] 5Bh[2:0] 59h[7:0],
VOFF[8:0] 5Bh[4] 5Ah[7:0] and FOFF[5Bh[7]].
Contrary to the scalers counting, the slicers offsets define the position of the H and V
trigger events related to the processed video field. The trigger events are the falling edge
of HREF and the falling edge of V123 from the decoder processing part.
The relationship of these programming values to the input signal and the recommended
values are given in
Table 15:
DT[3:0]
62h[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
Standard type
teletext EuroWST, CCST
European closed caption
VPS
wide screen signalling bits 5
US teletext (WST)
US closed caption
(line 21)
(video data selected)
(raw data selected)
teletext
VITC/EBU time codes
(Europe)
VITC/SMPTE time codes
(USA)
reserved
US NABTS
Data types supported by the data slicer block
Figure 28
Rev. 03 — 16 February 2006
and
Multistandard video decoder with adaptive comb filter
Figure
Data rate
(Mbit/s)
6.9375
0.500
5
5.7272
0.503
5
5
6.9375
1.8125
1.7898
5.7272
2
29.
4 bit programming bits).
Framing Code
(FC)
27h
001
9951h
1E 3C1Fh
27h
001
none
none
programmable
programmable
programmable
programmable
56 bytes (2
Table
15.
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
14 Dwords). The clock
FC window Hamming
WST625
CC625
VPS
WSS
WST525
CC525
disable
disable
general text
VITC625
VITC525
NABTS
SAF7118
check
always
always
optional
optional
61 of 170