SSM-Clock Stamp – Stamp Format (1.1)

One-line ASCII stamp (canonical shape)
SSMCLOCK1|iso_utc|rasi_idx|theta_deg|sha256(file)|chain[|kv:...]

Field definitions (must)

  • iso_utc — UTC timestamp YYYY-MM-DDThh:mm:ssZ (no subseconds, no offsets).
  • rasi_idx — integer in [0,11].
  • theta_deg — decimal degrees in [0,360), rendered with exactly theta_prec digits (default 5) using IEEE-754 binary64 round-half-to-even.
  • sha256(file) — lowercase 64-hex digest of the file bytes. Label note: the field name remains sha256(file) for compatibility; the actual algorithm is declared via kv:algo (default sha256).
  • chain — lowercase 64-hex digest defined by the append-only rule (see 1.4), computed with kv:chain_algo (default sha256).

Optional tail (non-breaking)
After chain, a kv: list may follow:
|kv:algo=sha256;chain_algo=sha256;theta_prec=5;float=ieee75464;time_mode=derived_utc;...

  • Keys are ;-separated key=value pairs (ASCII).
  • Parsers MUST ignore unknown keys (forward-compatible).
  • See 1.8 for allowed keys and acceptance rules.

ASCII line discipline (shape)
Single line; | is the only field separator. No spaces. No leading or trailing separators:
SSMCLOCK1|iso_utc|rasi_idx|theta_deg|sha256(file)|chain

Compatibility
Earlier stamps remain valid under these rules; the base fields are unchanged and kv: provides forward-compatible agility.

Navigation
Back: SSM-Clock Stamp – Normative Specification — Stamp (1)
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