SEL-MDX1
Installation and Operation Manual
17
Copyright © 2011, Harris Corporation
ASI-188-VBR
and
ASI-204-VBR
use an Asynchronous Serial Interface (ASI) with a variable
bit rate. The downstream receiver must be explicitly configured to use either 188-byte, or
204-byte packets, as per this setting. The module reads packets out of its buffer at the
highest variable rate possible (therefore variable) without exceeding the configured
Output
Rate
. No null packets are inserted, so the resulting stream may not consume the entire
configured rate.
SMPTE-310M
carries MPH (mobile/pedestrian/handheld) information. The module reads
packets out of its buffer at a constant rate and inserts null transport stream packets or
opportunistic data to bring the output rate of the multiplex up to the SMPTE-310M rate
(19.39265846 Mbps with 188-byte packets).
Passthrough
This parameter specifies whether to bypass the port’s multiplexer.
When
Enable
is selected, the interface transmits one multi-program transport stream as
input and makes that stream available on one VC, which may then serve as a cross-
connection source. The
Disable
option multiplexes the input stream into one or more
single-program transport streams. Each program may be directed to its own VC and each
such VC may serve as a cross connection source.
If more than one VC is configured to operate on this interface, only the first VC is used, and
a configuration alarm is raised. To clear the alarm, delete all but one VC and then
Enable
this control.
Output Rate
This parameter sets the output bit rate of the transport stream The range is
0
to
214
Mb/s,
but this is limited by the standard selected.
0
to
213.72
is the range of available when the
Standard
parameter is set to either
ASI-188-CBR
or
ASI-188-VBR
. (When using this
Standard
setting, every 8-bit byte
occupies 10 bits on the physical medium. Additionally, packets are separated by 2
padding bytes.
Using this format, the carrier rate (or raw bandwidth) for a given transport stream rate
is the following:
carrier_rate = ts_rate * (10/8) * (190/188)
213.7263158 = 270 * (8/10) * (188/190)
0
to
197.12
is the range of rates when the
Standard
is set to either
ASI-204-CBR
or
ASI-204-VBR
. Every 8-bit byte occupies 10 bits on the physical medium. Additionally,
packets are separated by 2 padding bytes. Finally, the rate is computed for 188-byte
packets, even though 204 bytes of data are present.
Using this format, the carrier rate (or raw bandwidth) for a given transport stream rate
is the following:
carrier_rate = ts_rate * (10/8) * (206/204) * (204/188)
197.1262136 = 270 * (8/10) * (204/206) * (188/204)
0
to
19.39
is the range of rates when the
Standard
is set to SMPTE-310M.
SI Mode
Use this field to specify the
system information table paradigm.
