ADV7180
The user may select the data identification word (DID) and the
secondary data identification word (SDID) through
programming the ADF_DID[4:0] and ADF_SDID[5:0] bits,
respectively, as explained in the following sections.
VDP_TTXT_TYPE_MAN_ENABLE, Enable Manual
Selection of Teletext Type, Address 0x60 [2], User Sub Map
0 (default)—Manual programming of the teletext type is
disabled.
ADF_DID[4:0], User-Specified Data ID Word in Ancillary
Data, Address 0x62 [4:0], User Sub Map
1—Manual programming of the teletext type is enabled.
VDP_TTXT_TYPE_MAN[1:0], Specify the Teletext Type,
Address 0x60 [1:0], User Sub Map
This bit selects the data ID word to be inserted into the
ancillary data stream with the data decoded by the VDP.
These bits specify the teletext type to be decoded. These bits are
functional only if VDP_TTXT_TYPE_MAN_ENABLE is set to 1.
The default value of ADF_DID[4:0] is 10101.
ADF_SDID[5:0], User-Specified Secondary Data ID Word
in Ancillary Data, Address 0x63 [5:0], User Sub Map
Table 68. VDP_TTXT_TYPE_MAN Function
VDP_TTXT_
TYPE_MAN[1:0]
These bits select the secondary data ID word to be inserted in
the ancillary data stream with the data decoded by the VDP.
625/50 (PAL)
525/60 (NTSC)
00 (default)
Teletext-ITU-BT.653-
625/50-A
Reserved
The default value of ADF_SDID[5:0] is 101010.
01
10
Teletext-ITU-BT.653-
625/50-B (WST)
Teletext-ITU-BT.653-
625/50-C
Teletext-ITU-BT.653-
525/60-B
Teletext-ITU-BT.653-
525/60-C or EIA516
(NABTS)
DUPLICATE_ADF, Enable Duplication/Spreading of
Ancillary Data over Y and C Buses, Address 0x63 [7], User
Sub Map
This bit determines whether the ancillary data is duplicated
over both Y and C buses or if the data packets are spread
between the two channels.
11
Teletext-ITU-BT.653-
625/50-D
Teletext-ITU-BT.653-
525/60-D
VDP Ancillary Data Output
0 (default)—The ancillary data packet is spread across the Y and
C data streams.
Reading the data back via I2C may not be feasible for VBI data
standards with high data rates (for example, teletext). An
alternative is to place the sliced data in a packet in the line
blanking of the digital output CCIR656 stream. This is available
for all standards sliced by the VDP module.
1—The ancillary data packet is duplicated on the Y and C data
streams.
ADF_MODE[1:0], Determine the Ancillary Data Output
Mode, Address 0x62 [6:5], User Sub Map
When data has been sliced on a given line, the corresponding
ancillary data packet is placed immediately after the next EAV
code that occurs at the output (that is, data sliced from multiple
lines are not buffered up and then emitted in a burst). Note that,
due to the vertical delay through the comb filters, the line
number on which the packet is placed differs from the line
number on which the data was sliced.
These bits determine if the ancillary data output mode is in byte
mode or nibble mode.
Table 69.
ADF_MODE[1:0]
Description
00 (default)
Nibble mode
01
10
Byte mode, no code restrictions
The user can enable or disable the insertion of VDP decoded
results into the 656 ancillary streams by using the
ADF_ENABLE bit.
Byte mode, but 0x00 and 0xFF prevented
(0x00 replaced by 0x01, 0xFF replaced by
0xFE)
11
Reserved
ADF_ENABLE, Enable Ancillary Data Output Through
656 Stream, Address 0x62 [7], User Sub Map
0 (default)—Disables insertion of VBI decoded data into
ancillary 656 stream.
1—Enables insertion of VBI decoded data into ancillary 656
stream.
Rev. A | Page 53 of 112
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