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76 lines
2.2 KiB
Plaintext
76 lines
2.2 KiB
Plaintext
To allow the transport of DVB-S2 baseband frames (BBFrame) across existing hard- and software
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interfaces, we have added the ability to embed the BBFrame data into a MPEG2 transport stream.
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This is available on supported cards as firmware update.
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This feature is currently considered experimental.
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Supported hardware:
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Cine V7A (>=1.7 FW)
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OctopusCI S2 Pro Advanced (>=1.7 FW)
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Duoflex S2 v4 Advanced (TBA)
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The following cards are based on the broadcast version of the
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DVB-S2 demodulator. The BBFrame output is working but
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not documented. We therefore can not guarantee the
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feature will work under all conditions.
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cineS2 V7 (>=1.7 FW)
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OctopusCI S2 Pro (>=1.7 FW)
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Duoflex S2 v4 (TBA)
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Packet format:
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The BBFrames are packetized into MPEG2 private sections (0x80), one section per transport stream
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packet. The PID is fixed at 0x010E.
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Header packet of frame:
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0x47 0x41 0x0E 0x1X 0x00 0x80 0x00 L 0xB8 BBHeader (169 * Data)
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L: Section Length, always 180 (0xB4)
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BBHeader: 10 Bytes BBFrame header (see DVB-S2, EN-302307)
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Data: 169 Bytes of BBFrame payload
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Payload packets:
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0x47 0x41 0x0E 0x1X 0x00 0x80 0x00 L N (179 * Data)
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L: Section Length, always 180 (0xB4)
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N: Packet counter, starting with 0x01 after header packet
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Data: 179 Bytes of BBFrame payload
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Last packet:
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0x47 0x41 0x0E 0x1X 0x00 0x80 0x00 L N ((L-1) * Data) ((180 – L) * 0xFF)
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L: Section Length, remaining Data – 1, (0x01 .. 0xB4)
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N: Packet counter
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Data: L-1 Bytes of BBFrame payload
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Automatic detection of input format:
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The bridge firmware allows automatic detection of the incoming data.
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To receive regular transport streams in this formats it is still required to setup
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the DVB-S2 demodulator to output BBFrames instead of regular TS Packets.
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When enabled the embedding mode is automatically turned on or off depending on incoming data
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from the DVB-S2/S2X frontend. The decision depends currently only on the first byte of a packet.
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If it is 0x47 it switches to transport stream mode else it switches to embedding mode.
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Note that 0x47 can currently not occur in the first byte of a BBFrame header if all reserved
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values of DVB-S2 and -S2X are observed.
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API:
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Currently DTV_STREAM_ID is misused.
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Set it to 0x80000000 to enable frame mode in the demod.
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