scope:

STANAG 4222 applies to the shipboard environment and is intended for intra-ship digital data communications between devices, equipments, sub-systems, or systems which contain at least a modest data processing capability such as a micro-processor with firmware.

The objective of STANAG 4222 is to provide a means by which elements of data can be communicated between two or more parties and be readily interpreted and understood by all parties to have the same meaning. To achieve this objective, it specifies standard units of measure for physical parameters, measurement conventions for linear and vector quantities, and rules which standardize certain binary notations for the representation of numbers, discrete data, alpha-numeric data (including non-printing characters), and binary-coded-decimal numbers (including some algebraic characters). Each parameter listed in the standard has specified for it a unique decimal identifying code.

The Standard does not address the format, structure, or syntax of data messages, which should properly be the subject of other documentation, but provides a vocabulary of individual parameters, and specifies the way in which their quantitative attributes shall be represented in the naval intra-ship environment.

Transmission of data is not the direct concern of this standard, but the progress towards 8-bit byte transmission fields, and the near universal adoption of 8-bit multiples for the word lengths used in processing devices has determined the adoption of the 8-bit byte (octet) as the elemental formatting unit, giving considerable independence and flexibility of word length in the source process, destination process, and communication process, with minimal data packing inefficiencies.