Data Types - Texas Instruments TI-89 Developer's Manual

14.

Data Types

The TI AMS Operating System (OS) supports the following data types:
Expressions
•
Lists
•
• Matrices
• Data Variables
Text Variables
•
Strings
•
Graph Databases
•
Pictures
•
Programs
•
• Functions
• Assembly Programs
Third Party Data Types (FILEs)
•
Note that there are two additional data types: figures and macros. They are only
supported by the, at one time, built-in geometry application which is now a
separate application.
This chapter defines the structure of the data objects that may appear in each of
the above data types. These data objects all have an embedded tag value which
is always the last value stored in a data object. The first word (Most Significant
Byte first) of every data object is the length of the object. This length does not
include itself, so to find the tag associated with any object, add the length of the
object to the starting address of the object plus one. There is a routine, HToESI,
that given the handle of a data object will return a pointer to the tag byte for that
object. Shown below is a list of the data tag values along with other associated
tags (END_TAG, COMMAND_TAG, END_OF_SEGMENT).
TI-89 / TI-92 Plus Developer Guide Not for Distribution
145
Beta Version January 26, 2001