1311 if present the transfer frame secondary header

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Unformatted text preview: in the Transfer Frame Primary Header (see 4.1.2.7.2). 4.1.3.1.3 The Transfer Frame Secondary Header shall consist of an integral number of octets as follows: a) Transfer Frame Secondary Header Identification Field (1 octet, mandatory); b) Transfer Frame Secondary Header Data Field (1 to 63 octets, mandatory). 4.1.3.1.4 If present, the Transfer Frame Secondary Header shall be associated with either a Master Channel or a Virtual Channel. NOTE – The association of a Transfer Frame Secondary Header with a Master Channel allows data to be transferred synchronized with this Master Channel. The association of a Transfer Frame Secondary Header with a Virtual Channel allows data to be transferred synchronized with this Virtual Channel. 4.1.3.1.5 If present, this field shall occur within every Transfer Frame transmitted through the associated Master or Virtual Channel throughout a Mission Phase. CCSDS 132.0-B-1 Page 4-8 September 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL 4.1.3.1.6 The Transfer Frame Secondary Header shall be of fixed length within the associated Master or Virtual Channel throughout a Mission Phase. The format of the Transfer Frame Secondary Header is shown in figure 4-4. TRANSFER FRAME SECONDARY HEADER (up to 64 octets) TRANSFER FRAME SECONDARY HEADER ID TRANSFER FRAME SECONDARY HEADER VERSION NUMBER TRANSFER FRAME SECONDARY HEADER LENGTH 2 bits TRANSFER FRAME SECONDARY HEADER DATA FIELD 6 bits 1 octet up to 63 octets Figure 4-4: Transfer Frame Secondary Header 4.1.3.2 Transfer Frame Secondary Header Identification Field 4.1.3.2.1 General 4.1.3.2.1.1 Bits 0–7 of the Transfer Frame Secondary Header shall contain the Transfer Frame Secondary Header Identification Field. 4.1.3.2.1.2 The Transfer Frame Secondary Header Identification Field shall be sub-divided into two sub-fields as follows: a) Transfer Frame Secondary Header Version Number (2 bits, mandatory); b) Transfer Frame Secondary Header Length (6 bits, mandatory). 4.1.3.2.2 Transfer F...
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