It shall be 1 if a transfer frame secondary header is

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Unformatted text preview: sociation, see 4.1.3. 4.1.2.7.3 4.1.2.7.3.1 Flag. Synchronization Flag Bit 33 of the Transfer Frame Primary Header shall contain the Synchronization 4.1.2.7.3.2 The Synchronization Flag shall signal the type of data which are inserted into the Transfer Frame Data Field. It shall be ‘0’ if octet-synchronized and forward-ordered Packets or Idle Data are inserted; it shall be ‘1’ if a VCA_SDU is inserted. 4.1.2.7.3.3 The Synchronization Flag shall be static within a specific Virtual Channel throughout a Mission Phase. 4.1.2.7.4 Packet Order Flag Bit 34 of the Transfer Frame Primary Header shall contain the Packet Order Flag. CCSDS 132.0-B-1 Page 4-6 September 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL NOTE – If the Synchronization Flag is set to ‘0’, the Packet Order Flag is reserved for future use by the CCSDS and shall be set to ‘0’. If the Synchronization Flag is set to ‘1’, the use of the Packet Order Flag is undefined. 4.1.2.7.5 Segment Length Identifier 4.1.2.7.5.1 Bits 35 and 36 of the Transfer Frame Primary Header shall contain the Segment Length Identifier. 4.1.2.7.5.2 set to ‘11’. If the Synchronization Flag is set to ‘0’, the Segment Length Identifier shall be NOTES 1 This Identifier was required for earlier versions of this Recommendation to allow for the use of Source Packet Segments, which are no longer defined. Its value has been set to the value used to denote non-use of Source Packet Segments in previous versions. 2 If the Synchronization Flag is set to ‘1’, then the Segment Length Identifier is undefined. 4.1.2.7.6 4.1.2.7.6.1 Pointer. First Header Pointer Bits 37–47 of the Transfer Frame Primary Header shall contain the First Header 4.1.2.7.6.2 If the Synchronization Flag is set to ‘0’, the First Header Pointer shall contain the position of the first octet of the first Packet that starts in the Transfer Frame Data Field. NOTE – If the Synchronization Flag is set to ‘1’, then the First Header Pointer is undefined....
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