Overview
ISO 14962:1997 - "Space data and information transfer systems - ASCII encoded English" formalizes the use of ASCII-encoded English for exchange of textual data in space systems. It adopts CCSDS 643.0-B-1 (November 1992) and defines the character set, control-character interpretation and presentation rules so that human-readable English content (descriptions, labels, tables, figures, logs) is consistently encoded, transmitted and displayed across spacecraft and ground systems.
Key topics and technical requirements
- Adoption of CCSDS recommendation: ISO 14962 incorporates CCSDS 643.0‑B‑1 as the normative reference for ASCII encoded English in space data systems.
- Character set: Use of 7‑bit ASCII characters embedded in an 8‑bit field (most significant bit set to zero), consistent with ISO/IEC 646:1991.
- ADID identifier: The language/format identifier used is ADID = CCSD0002 (ASCII encoded English).
- Inactive/shaded characters: Certain ASCII positions are designated as without effect for presentation; these characters should not be displayed or printed.
- Control-character presentation rules:
- Line termination is standardized: interpreted from combinations of CR (carriage return) and LF (line feed) in defined ways (CR alone, LF alone, CR+LF, LF+CR as specified).
- Horizontal tab (HT) advances to the next tab stop at multiples of 8 character positions (0, 8, 16, 24, ...).
- Form feed (FF) moves to the top of the next page/screen; page length is device-defined.
- Devices may need to adjust presentation when device constraints (e.g., line length) conflict with data layout.
- Presentation guidance: For data where fixed alignment matters (tables, ASCII art), a fixed‑width font is recommended.
Applications and who uses it
ISO 14962 is intended for use by organizations and professionals involved in space data exchange and interoperability, including:
- Spacecraft systems engineers and mission architects
- Ground-segment developers and telemetry/telecommand software teams
- Data format designers using Standard Formatted Data Units (SFDU)
- Instrument teams creating human-readable metadata, logs and reports
- Standards bodies and agencies coordinating multi-agency missions (NASA, ESA, CNES, etc.)
Typical practical uses:
- Encoding human-readable fields in mission data packets and SFDU payloads
- Ensuring consistent rendering of ASCII tables, logs and diagnostic output across heterogeneous platforms
- Facilitating international interoperability and archival of mission textual data
Related standards
- CCSDS 643.0‑B‑1 (Recommendation: ASCII encoded English) - normative source adopted by ISO 14962
- ISO/IEC 646:1991 - character set reference for international 7/8‑bit codes
- CCSDS 620.0‑B‑2 and 621.0‑G‑1 - SFDU structure and tutorial referenced for integrating ASCII content into formatted data units
Keywords: ISO 14962, ASCII encoded English, CCSDS 643.0‑B‑1, space data systems, SFDU, ISO 646, space telemetry, data interoperability.
