evertz 8074 Manual

The following document describes the operational changes to the 8074 related to firmware version
990715. References to the 8074 manual are to version 1.0 printed February 1998.
1. Overview of New Features
•
Serial Port B may be configured to echo out serial commands received through other serial ports.
•
Closed caption data may be extracted and output directly to serial port B.
•
Closed caption data may be input through port B and inserted directly into the outgoing SDI video.
•
Text article line length has been increased to accommodate longer WebTV links.
2. Port Passthrough Features
Through the Engineering Setup menu system, the user may now place the 8074 into one of several
serial port passthrough modes. The new modes are referred to as "Port Passthrough" and "Caption
Data Passthrough". These modes allow control commands or closed caption data to be cascaded from
one 8074 to another through the serial ports. This functionality is useful for copying captions from one
video stream to another, or to re-insert captions that have been removed or damaged by processing
operations.
All of the new port B passthrough modes require port B of the 8074 unit to be connected to a serial
port of another 8074, an 8075 or an 8070 depending on the application.
2.1 Port Echo Modes
These modes cause serial commands received on the respective serial port or modem port to be
echoed out of serial port B. These commands may then be cascaded to a second 8074 using a serial
interface cable as described in section 2.3. The successive unit(s) will then receive the same serial
commands as the first unit, after a slight propagation delay. The receiving unit does not need to be
placed in a special operating mode, and may be another 8074, an 8075 or an 8070 unit.
The following figure depicts a typical configuration to use the Port Echo Modes.
Date of Issue: July 15, 1999
Model 8074 Digital Video Closed Caption Encoder Manual
Captioning Computer
8074
SDI In
"Port Echo Mode"
8074
SDI In
"Port Echo Mode"
8070/8074/8075
SDI In
Figure 1: Connections for Port Echo Mode
Copyright Evertz Microsystems Ltd. All rights reserved
8074 Manual Change Sheet 1.0-2
Port A, C or D
SDI Out
Port B
Port A or C
SDI Out
Port B
Any serial port
SDI Out
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