Input Xds - evertz 8084 Instruction Manual

SERIAL PROTOCOL
Models 8084/8084AD/8085 Closed Caption Encoder Manual
The XDS output stream consists of a distinct XDS packet for each type of
information. Each packet consists of a 1 byte class, a 1 byte type, one or
more informational characters, a 1 byte end of packet code, and a 1 byte
checksum.
XDS packets are stored in the article memory and output in the XDS data
channel in Field 2. These packets are placed into the XDS output queue in
the order specified by the user and inserted into Field 2 according to the
space available. EIA-608-B specifies that when there is caption or XDS
information in field 2, then there must be at least a null caption signal
present in field 1 as well.
automatically detects whether there is a caption signal present in field 1. If
necessary It will turn on the Field 1 keyer automatically (the FIELD ! LED
will blink) and turn it off again when upstream field 1 captions resume.
The computer uses an ASCII hex notation in describing the XDS packet id
and data to the caption encoder. For example to specify the letter A enter
a 4 followed by a 1 (the hex ASCII code for A is 41)
The XDS packets are deleted from memory when they have been
transmitted the specified number of times. XDS packets will be lost from
the encoder's memory in the event of a power loss. The 8084 and 8084AD
use an advanced memory allocation scheme that allow them to store a
virtually unlimited number of XDS packets at one time. The only limit is the
total amount of random access memory available.
Upstream XDS packets will be blocked by packets of the same type in the
output queue.
4.6.1

Input XDS

This command allows the user to input an XDS packet into the caption
encoder's article memory
If an XDS packet with identical edsid exists it will be deleted and replaced
with the new packet definition.
Command: ^AP<sp>edsid<sp>rc<sp>data...data<cr>
Default none
The parameter edsid identifies the XDS packet id. The XDS packet can
subsequently be referred to by its packet id. If the XDS packet already
exists, the previous XDS packet with that packet id will be replaced by the
new packet. The edsid is entered in ASCII hex notation. For example to
enter a packet id with a class of 01h and a type of 23h enter a 0 followed
by a 1 followed by a 2 followed by a 3. The leading zero of the class is
optional.
Revision 1.6.6
When encoding into field 2, the 8084AD
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