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>PORT B FUNCTION
Funct B Normal
Funct B ATSC
Funct B ATSC GA
>PORT B DELAY
Delay B = 31 fr
OPERATION
Models 8084/8084AD/8085 Closed Caption Encoder Manual
PORT B FUNCTION is used to select the operating mode of the Port B
serial port.
Select Funct B Normal for standard interface to captioning computers and
software.
Select Funct B ATSC for interfacting Port B to ATSC compression
encoders using the SMPTE 333M protocol at 38400 bps. The
8085 Port B communication parameters will be changed to
38400 baud, 8 bits, No Parity. No other baud rate options or
word options will be available while in this functional mode. The
COMM light on the 8085 front panel will turn on when the ATSC
encoder sends a valid polling character.
Select Funct B ATSC GA
encoders using the original, Grand Alliance, uni-directional
protocol at 19200 bps. The 8085 Port B communication
parameters will be changed to 19200 baud, 8 bits, No Parity.
No other baud rate options or word options will be available
while in this functional mode. The COMM light on the 8085 front
panel will turn on continuously when this mode, since the 8085
is unilaterally broadcasting the packet data.
An additional delay may be added to the ATSC interface data. This delay
can offset other processing delays in the ATSC video path.
Engineering Setup menu item has been added called >PORT B DELAY.
This menu is accessed by entering the Engineering Setup menus using the
SHIFT+SETUP key combination. Then use the up arrow until the >PORT
B DELAY prompt is displayed.
PORT B DELAY is used to select the ATSC packet data delay of the Port
B serial port. When set to zero, the 8085 will encode and
transmit the ATSC packet as soon as possible (there will likely
be a small, unavoidable delay due to the 8085 processing, the
transmission delay, and the ATSC processing). When set to the
maximum of 31 frames, the 8085 will delay the ATSC packet
data by 31 video frames.
Select Delay B 0 fr
for minimum data delay through the 8085
Select Delay B 31 fr for maximum data delay through the 8085
Revision 1.6.6
for interfacing Port B to ATSC compression
A new
Page 3-21
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