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Unformatted text preview: be used by Agencies or
Centers for local enhancements to TC operations and is not part of the COP
protocol. (4) COP IN EFFECT (Bits 6,7)
These two bits indicate the COP which is being used. At present a single COP,
COP-1, is defined. It shall be identified by setting Bits 6,7 to the binary value “01”. (5) VIRTUAL CHANNEL ID (Bits 8-13)
This field contains the VIRTUAL CHANNEL Identifier of the TC Virtual Channel
with which this report is associated. Each Virtual Channel which is open shall have
its own CLCW reporting activated. (6) RESERVED SPARES (Bits 14,15)
These two bits are reserved by CCSDS for future application. For the present, Bits
14,15 shall be set to value “00”. (7) FLAGS (Bits 16,17,18,19,20)
(a) NO RF AVAILABLE flag (Bit 16)
The NO RF AVAILABLE flag provides a logical indication of the “ready”
status of the radio frequency (rf) elements within the physical data channel
provided by the Channel Service layers. Precise definition of the set of
physical states which must each be in the “ready” condition before
commanding is possible is mission-specified. For example, the flag can
represent a logical sum of the overall ready status of components such as the
rf transponder and the demodulator. CCSDS 202.0-B-2 Page 4-11 CCSDS HISTORICAL DOCUMENT November 1992 CCSDS HISTORICAL DOCUMENT
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA ROUTING SERVICE Whenever Bit 16 is set to value “0”, the physical channel is AVAILABLE
(i.e., any TC Transfer Frame will be received and processed by the Channel
Service layers and passed on to the Transfer layer if correct).
Whenever Bit 16 is set to value “1”, the physical channel is NOT
AVAILABLE and TC Transfer Frames cannot be transferred without
corrective action within the Channel Service layers.
The single NO RF AVAILABLE flag applies to all Virtual Channels. This
input parameter to the CLCW is updated whenever a change is signaled by the
(b) NO BIT LOCK flag (Bit 17)
The NO BIT LOCK flag is an optional, mission-specific engineering
measurement which provides a performance quality indicator that indicates
specifically whether the Channel S...
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This document was uploaded on 03/06/2014.
- Spring '14