TI variable file
TI variable file is a family of file formats used for transfering data to or from Texas Instruments calculators. There is a version of the format for each model of calculator, and within each version there is a format for each type of variable.
See also TI picture file.
Well over 100 different filename extensions are used. In general, the first two characters of the extension indicate the calculator model, and the third character indicates the data type. For example, .89p is a Program in TI-89 format.
TI variable files begin with an 8 byte ASCII signature that starts with "
**TI" and indicates the version or model, for example "
**TI92**" or "
**TI83F*". The next two or three bytes may also be considered to be part of the file signature, depending on the version.