BS ISO 11104 pdf download Space data and information transfer systems — Time code formats
This International Standard establishes a small number of standardized recommended time code formats foruse in data interchange applications between agencies of the CCSDS. This International Standard does notaddress timing performance issues such as stability,precision, accuracy, etc.
Time codes are digital representations of time information. This International Standard describes four standardrecommended time codes (one “unsegmented” and three “segmented” codes)which use the internationalstandard second as the fundamental unit of time. An unsegmented time code is a pure binary count of timeunits and fractional time units from a starting time called the “epoch”. A segmented time code is one in whichthe count of time units and fractional time units is accumulated in two or more cascaded counters which countmodulo of various bases and start from the epoch.
The scope and field of application are furthermore detailed in subclauses 1.2 to 1.4 of the enclosed cCSDspublication.
Requirements are the technical recommendations made in the following publication (reproduced on thefollowing pages), which is adopted as an International Standard:
ccsDS 301.0-B-4,November 2010，Time code formats.
For the purposes of international standardization, the modifications outlined below shall apply to the specificclauses and paragraphs of publication ccsDS 301.0-B-4.
Pages i to v
This part is information which is relevant to the CCsDs publication only.
3Revision of publication ccsDS 301.0-B-4
lt has been agreed with the Consultative Committee for Space Data Systems that SubcommitteeISO/Tc 20/Sc 13 will be consulted in the event of any ‘revision or amendment of publicationccSDS 301.0-B-4.To this end,NASA will act as a liaison body between ccsDs and lSo.