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The user must ensure that the port B baud rate of the two caption encoders is identical. 9600 baud is
the minimum recommended speed. Data width and parity are set automatically in VBI bridge modes.
If the user's application requires that the pre-encoded captions must be multiplexed with new caption
data, XDS, V-Chip or WebTV URLs, we recommend that the "CC transmit" encoder should be used for
this purpose. Starting with 8084 and 8084AD firmware dated R010621, the "CC receive" encoder can
also perform other captioning functions as well as re-encode data as a VBI Bridge.
performing these functions in the transmit-side encoder will maintain maximum compatibility with our
older 8074 line of closed caption encoders. These units also support the VBI bridge functionality, but a
receive-side 8074 encoder cannot insert other new data when it is performing a VBI bridge function.
To configure the 8084 or 8084AD for VBI bridging using method 2 perform the following steps.
Set the upstream encoder to CC Transmit operation (to extract caption data prior to DVE):
•
Enter Engineering Setup menu system by pressing SHIFT+SETUP
•
Press UP or DOWN arrows until display shows >PORT B FUNCTION
•
Press LEFT or RIGHT arrows until display shows Funct B CC xmit
•
Press SELECT button. CC xmit will now be flashing to indicate that this mode is selected.
•
Exit the Engineering Setup menu system by pressing SETUP
Set the downstream encoder to CC Receive Operation (to re-insert caption data after DVE):
•
Enter Engineering Setup menu system by pressing SHIFT+SETUP
•
Press UP or DOWN arrows until display shows >PORT B FUNCTION
•
Press LEFT or RIGHT arrows until display shows Funct B CC recv
•
Press SELECT button. CC recv will now be flashing to indicate that this mode is selected.
•
Exit the Engineering Setup menu system by pressing SETUP
Set the Port B baud rates the same on the Transmit and Receive encoders.
•
Enter Engineering Setup menu system by pressing SHIFT+SETUP
•
Press UP or DOWN arrows until display shows >PORT B BAUD
•
Pressing LEFT or RIGHT arrows will change the display to BaudB=xxxx
•
Set the baud rate to 9600 baud or higher by pressing the LEFT or RIGHT arrow keys.
•
Press SELECT button. The selected baud rate will now be flashing.
•
Exit the Engineering Setup menu system by pressing SETUP
A.3.3 Method 3: Evertz Encoder and SoftTouch Hubcap
Figure A-4 shows how the VBI bridge can also be implemented using a SoftTouch Hubcap
decoder to extract caption data, instead of an Evertz encoder. The Hubcap may be configured to
extract only field 1 or both fields 1 and 2 data in this configuration. Please refer to documentation
supplied by SoftTouch for configuring the Hubcap decoder. Because the Hubcap processes composite
analog video, not digital video, a composite encoder device is required to perform the digital-to-analog
conversion on the video feed to the Hubcap.
1
SoftTouch, Hubcap, MagHubcap names and image used with permission of SoftTouch, Inc.
6196 Oxon Hill Road, Oxon Hill, MD 20745-3100
APPLICATION NOTE 2
Models 8084/8084AD/8085 Closed Caption Encoder Manual
Revision 1.6.6
However,
1
caption
AN2-4
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