412233 the spacecraft identifier shall be static

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Unformatted text preview: 2–14 of the Transfer Frame Primary Header shall contain the Virtual Channel Identifier (VCID). NOTES 1 The Virtual Channel Identifier provides the identification of the Virtual Channel. 2 There are no restrictions on the selection of Virtual Channel Identifiers. In particular, Virtual Channels are not required to be numbered consecutively. 4.1.2.4 Operational Control Field Flag 4.1.2.4.1 Bit 15 of the Transfer Frame Primary Header shall contain the Operational Control Field Flag. 4.1.2.4.2 The Operational Control Field Flag shall indicate the presence or absence of the Operational Control Field. It shall be ‘1’ if the Operational Control Field is present; it shall be ‘0’ if the Operational Control Field is not present. 4.1.2.4.3 The Operational Control Field Flag shall be static within the associated Master or Virtual Channel throughout a Mission Phase. NOTE – For the significance of the above-mentioned association, see 4.1.5. 4.1.2.5 Master Channel Frame Count 4.1.2.5.1 Bits 16–23 of the Transfer Frame Primary Header shall contain the Master Channel Frame Count. 4.1.2.5.2 This 8-bit field shall contain a sequential binary count (modulo-256) of each Transfer Frame transmitted within a specific Master Channel. 4.1.2.5.3 A re-setting of the Master Channel Frame Count before reaching 255 shall not take place unless it is unavoidable. NOTE – The purpose of this field is to provide a running count of the Transfer Frames which have been transmitted through the same Master Channel. If the Master Channel Frame Count is re-set because of an unavoidable re-initialization, then the completeness of a sequence of Transfer Frames in the related Master Channel cannot be determined. CCSDS 132.0-B-1 Page 4-4 September 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL 4.1.2.6 Virtual Channel Frame Count 4.1.2.6.1 Bits 24–31 of the Transfer Frame Primary Header shall contain the Virtual Channel Frame Count. 4.1.2.6.2 This 8-bit field shall contain a sequential binary count (modulo-256) of each...
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This document was uploaded on 03/06/2014.

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