Note the controlling specification for how the clcw

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Unformatted text preview: ts the status of frame acceptance to the Frame Operation Procedure (FOP) at the sending end of the Transfer layer. NOTE The controlling specification for how the CLCW is used within the COP is contained in Reference [7]. The CLCW is the only reporting mechanism for the TC Transfer layer. Although it is not necessary that the Telemetry reporting rate match the Telecommand transfer rate, some minimum CLCW sampling rate is necessary for the proper operation of the COP. The format of the CLCW is shown in Figure 4-3. CCSDS 202.0-B-2 Page 4-9 CCSDS HISTORICAL DOCUMENT November 1992 CCSDS HISTORICAL DOCUMENT CCSDS RECOMMENDATION FOR TELECOMMAND: DATA ROUTING SERVICE CONTROL WORD TYPE "0" CLCW VERSION "00" STATUS FIELD COP IN EFFECT VIRTUAL CHANNEL IDENTIFICATION SPARE 1 2 3 2 6 2 (ALWAYS "0" FOR CLCW) FLAGS NO RF AVAIL NO BIT LOCK LOCKOUT WAIT 1 1 1 FARM B RETRANSMIT COUNTER 1 1 2 SPARE REPORT VALUE 1 8 Figure 4-3: Command Link Control Word Format The CLCW contains the following fields: Field Length (Bits) CONTROL WORD TYPE CLCW VERSION STATUS FIELD COP IN EFFECT VIRTUAL CHANNEL ID RESERVED SPARE FLAGS: - No rf available (1) - No bit lock (1) - Lockout (1) - Wait (1) - Retransmit (1) FARM B COUNTER RESERVED SPARE REPORT VALUE CCSDS 202.0-B-2 1 2 3 2 6 2 5 2 1 8 32 bits (4 octets) Page 4-10 CCSDS HISTORICAL DOCUMENT November 1992 CCSDS HISTORICAL DOCUMENT CCSDS RECOMMENDATION FOR TELECOMMAND: DATA ROUTING SERVICE Unless otherwise stated, all fields are required elements. (1) CONTROL WORD TYPE (Bit 0) This one-bit field shall be set to zero to indicate that the Operational Control Field contains a CLCW. (2) CLCW VERSION NUMBER (Bits 1,2) The two-bit CLCW VERSION NUMBER field is included to provide future growth flexibility. However, at present a single “Version-1” CLCW format is defined in this Recommendation. It shall be indicated by setting Bits 1,2 to value “00”. The format of the Version-1 CLCW report is described herein. (3) STATUS FIELD (Bits 3,4,5) Application of this field is mission-specified. It may...
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This document was uploaded on 03/06/2014.

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