EN530 HDTV Smart Encoder IV
URL and Text Encoding
The EN530 handles URL and Text Encoding, like XDS, as an output from
memory function, rather than a real time flow function. The EN530 can store
up to 24 separate text messages and interactive television URLs in RAM
storage indefinitely. Messages in storage may be transmitted in any sequence
and repeated any number of times in either Field 1 text channel. However, both
channels cannot use the same message simultaneously. Once insertion of a
message begins, upstream data on that Text channel is blocked until the locally
inserted message is completed. The URL insertion protocol operates in T2 and
is fully compliant with EIA-608B specifications.
Begin Message Input
<CTRL+A>0 Title [Channel] [Repeat] [K/D] [O/H] [N/L] <ENTER>
End Message Input
<CTRL+C>
To load a new message, enter the Begin Message Input command. The
character following <CTRL+A> in the Begin command is a zero. The Encoder
should respond with “>” as a prompt at the beginning of the message and at the
beginning of each new line. Enter the message text, ending each line with a
carriage return (0Dh or <ENTER>). For URL insertion, be certain to observe
the format defined in EIA-608B, which includes specific ordering, punctuation,
and a checksum. When the message is finished, enter a final carriage return,
and then the End Message Input command.
To insert a transmission delay within the message, insert the command
<CTRL+B> Delay
at the desired point, setting Delay equal to the length of the
desired delay in seconds.
Title
sets the title of the message. The title will be used to identify the
message for future use.
Channel
sets the Text Channel queue (T1 or T2) into which the message
will be inserted. T1 is the default.
Repeat
sets the integer number of times that the message will be repeated
when it arrives in the queue. All messages in the queue are cycled, and any
message that has not reached its Repeat count returns to the end of the
queue line after it is inserted. The default setting is infinite repeat (listed as
FFFF in a status display).
K/D
specifies whether the article is to be Kept in memory or Deleted once
it exits the queue. The default setting is Delete.
O/H
instructs the Encoder to either Output the article to the appropriate
channel queue immediately or to Hold it in memory for future use.
Immediate output is the default setting.
©2000-2007 EEG Enterprises, Inc.
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