HD1492 HD Encoder Frame Card
The input text may be formatted to fit on 32 character lines by sending a
carriage return at word boundaries approaching the 32 character limit.
If sufficient data to fill a line is not available within a reasonable amount
of time, a carriage return should be sent to ensure timeliness for the
queued data.
Channel
Channel specifies which NTSC caption channel the
ASCII data that will be entered is intended for. En-
ter CC1 for primary language captioning or CC3
for secondary language captioning. If no parame-
ter is entered, CC1 will be assumed.
Rollup
Rollup sets the number of rows in the rollup cap-
tion display that will be created. Possible values
are 2, 3, and 4. If no setting is entered, 3 will be
assumed.
Base
Base sets the row from which the caption display
will begin rolling up. The parameter value must be
entered with a leading ‘b’. Possible values range
from b2 (top of the screen) to b15 (bottom of the
screen). The default value is b15. Always set the
Base value at least as large as the number of rows
in the rollup display, or else the uppermost row(s)
of the display will not be visible.
3.5
XDS Insertion
Extended Data Services (XDS) is an NTSC Field 2 data channel that
provides information to viewers about the program that is being aired.
XDS is used to transmit FCC-mandated program ratings to allow viewer
V-chip filtering. XDS is a part of the CEA-608 standard for SD broad-
casts, and should be included in the 608 compatibility bytes of CEA-708
compliant HD broadcasts.
XDS data packets can be loaded into the Encoder’s queue with one sim-
ple command, and be held for any specified time period. Each individual
packet type can be independently set for upstream or local priority, and
permanent packets can be stored in Non Volatile Memory and inserted
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