TR3271 Management Programming Manual

ELEMENTS OF SPI MESSAGES FOR THE SUBSYSTEM
Tokens
Tokens
The TR3271 subsystem uses tokens for parameters in commands,
responses to commands, and elements of event messages. Each
token has a token code and token value associated with it. A
token code is an identifying tag that programs refer to by name,
and a token value is a data item that programs also refer to by
name. The token code has two parts: a token type that specifies
the data type and length of the token value, and a token number
that uniquely identifies the token for the subsystem. See "Token
Types" in this section for a list of the token types used in the
TR3271 subsystem.
The actual token value can be in one of the following forms:
• A single field, such as an integer or a character string
• A fixed structure
• An extensible structure
Tokens that have a token value that is a single field or a
fixed structure are called simple tokens. Tokens that have a
token value that is an extensible structure are called extensible
structured tokens.
Simple Tokens
Simple tokens are tokens whose values are single fields or fixed
structures. The token codes for the simple tokens used by the
TR3271 subsystem are represented by symbolic names of the form
Z subsys -TKN- name , where subsys is a three-character subsystem
abbreviation and name identifies the token code. For example,
the token code ZEMS-TKN-LDEV identifies a simple token that
contains a logical device number. They are considered simple
tokens because you do not need a map to decode or build the
structure.
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