ST92195C STMicroelectronics, ST92195C Datasheet - Page 169

• Manufacturer Part Number: ST92195C
• Description: 48-96 Kbyte Rom Hcmos Mcu With On-screen Display And Teletext Data Slicer
• Manufacturer: STMicroelectronics

ST92195C/D - VPS & WSS SLICER
VPS & WSS SLICER (Cont’d)
7.8.6 WSS Data Group Assignments
into 4 groups. Group 1 contains 4 bits in which the
first 3 carry data and the last bit is the odd parity bit
for the first three bits. Group 2 contains 4 data bits.
Group 3 and Group 4 contain 3 data bits.
Group 1 Data: Aspect Ratio Bits
Bits 0, 1, and 2 are data bits with Bit 3 contains the
odd parity bit. The data bits in Group 1 are defined
in
Group 2 Data: Enhanced Service Bits
B(4)
B(7)-B(5)
Table 30. Group1 Data Bits
The number of active lines is only an indication for the exact aspect ratios a=1.33, a=1.56, and a=1.78.
tent to encourage a wide screen display on a 16:9 television set.
169/249
(*) The actual transmitted aspect ratio is 4:3 but a 14:9 window should contain all the relevant picture con-
The 14 data bits of the WSS signal are divided
B3
Table 30 Group1 Data
1
0
0
1
0
1
1
0
Film bit defined by: '0' is camera mode, '1'
is film mode.
Reserved. Set to “0”.
B2
0
0
0
0
1
1
1
1
B1
0
0
1
1
0
0
1
1
B0
0
1
0
1
0
1
0
1
Bits.
Aspect
>16:9
Ratio
14:9
14:9
16:9
16:9
14:9
16:9
4:3
Aspect Ratio Range
1.46 < a <= 1.66
1.46 < a <= 1.66
1.66 < a <= 1.90
1.66 < a <= 1.90
1.46 < a <= 1.66
1.66 < a <= 1.90
a<= 1.46
1.90 < a
Group 3 Data: Subtitle Bits
B(8)
B(9) and B(10) are Subtitling mode bits defined in
the following table:
Group 4 Data: Reserved Bits
B(13)-B(11)
b10
Letterbox
Letterbox
Letterbox
Letterbox
Letterbox
0
0
1
1
x
Format
Full (*)
Full
Full
b9
x
0
1
0
1
This bit denotes if subtitles are within the
teletext.
When “0”; Subtitles are NOT found within
teletext.
When “1”; Subtitles are found within tele-
text.
These bits are reserved. They are set to
“0”.
b8 Location of Subtitles
0
1
1
1
1
Not applicable
Not applicable
Position
No Subtitles in teletext
No open subtitles
Subtitles are in the active image area
Subtitles are out of the active image
area
Reserved
center
center
center
center
top
top
Number of Active Lines
(estimated)
not defined
576
504
504
430
430
576
576