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ST92195 ST92T195 ST92E195 - VPS & WSS SLICER
VPS & WSS SLICER (Cont’d)
7.8.3 About Video Programming System (VPS)
The VPS extracts the digital data from line 16 of a
transmitted PAL video signal. The VPS feature for
the VCR uses only 5 of the 13 bytes of information
to help simplify the programming of the VCR for re-
cording.
A total of 15 words is transmitted on field 1, line 16.
The signal is bi-phase modulated at a 2.5Mbit/s
rate. The VPS transmission specification defines
the clock frequency is 5MHz (+/-.01%), the signal
shape is sine squared pulses with half amplitude
pulse duration equal to 200ns +/- 10ns, and the
signal amplitude is 0.5V +/- 5%.
The first word starts 12.5 +/- 1.5 sync pulse. The
words (bytes) of data are recalled below:
Word 1: Run-in (10.10.10.10.10.10.10.10)
The run-in word is a group of all 1's. With the bi-
phase coding the signal is 1010101010101010
that is used for clock synchronisation inside the
VPS cell.
Word 2: Start code (10.00.10.10.10.01.10.01)
The start code helps to define the presence of
VPS and to synchronize the following data stream.
If the start code has not been recognised 12.7 +/-
0.2 the VPSWin rising edge, the system waits for
the next VPSWin to find a Start code.
Words 3 and 4 are not relevant for the VPS coding.
Word 5: Identification of sound channels and “Rat-
ed R” mark
Words 6 through 10 are not relevant for VPS coding.
Words 11 through 14 contain 32 bits. Complete in-
formation may involve bits contained in two bytes.
These bits are numbered from 0 to 31 in the VPS
transmission spec to show the order in reverse time
that the bits are actually transmitted. This means the
MSB is the first bit following the framing code for any
one grouping of information. The bit numbers are in-
cluded below to help cross-reference the bits with
the VPS transmission specification.
Word 15 is not relevant for VPS coding and is not
defined in the VPS specification.
ID of address Announced Day of Transmission (6 bits) (binary)
Announced Month of Transmission (4 bits) Announced Start Hour (5 bits) binary
Announced Start Minute (6 bits) Nationality (4 bits) (binary)
Nationality (4 bits) Program Source Code (6 bits)
VPS Bit #
-
------
Word 5
7
6
543210
Sound
R-rating
reserve
VPS01
SD(1)
SD(0)
RR(1)
RR(0)
RX(3)
RX(2)
RX(1)
RX(0)
Sound Bits
R-Rating Bits
Reserved Bits for future application
VPS Bit #
0
1
2
3
4
5
6
7
Word 11
7
6
5
4
3
2
1
0
ID
Day
Month
VPS02
ID(1)
ID(0)
ADT(4)
ADT(3)
ADT(2)
ADT(1)
ADT(0)
AMT(3)
VPS Bit #
8
9
10
11
12
13
14
15
Word 12
76543
21
0
Month
Hour
VPS03
AMT(2)
AMT(1)
AMT(0)
ASH(4)
ASH(3)
ASH(2)
ASH(1)
ASH (0)
VPS Bit #
16
17
18
19
20
21
22
23
Word 13
7
6
5
4
3
2
1
0
Minute
Nation
VPS04
ASM(5)
ASM(4)
ASM(3)
ASM(2)
ASM(1)
ASM(0)
NC (3)
NC (2)
VPS Bit #
24
25
262728293031
Word 14
7
6
543210
Nation
Source
VPS05
NC (1)
NC (0)
PSC(5)
PSC(4)
PSC(3)
PSC(2)
PSC(1)
PSC(0)