TI BASIC (TI 99/4A)

TI BASIC
ParadigmProcedural
First appeared1979; 45 years ago (1979)
Typing disciplineStatic, strong
LicenseProprietary

TI BASIC is an ANSI-compliant interpreter for the BASIC programming language built into the 1979 Texas Instruments TI-99/4 home computer and its improved 1981 version, the TI-99/4A.

In contrast to most BASICs found on contemporary microcomputers, TI BASIC does not trace its history to Microsoft BASIC, but was instead a TI-developed interpreter following the emerging Minimal BASIC standard being created by ANSI and ECMA. This was, in turn, based on the original Dartmouth BASIC from the 1960s. There are a number of differences, sometimes subtle, between TI BASIC and the more common MS varieties.

Minimal BASIC lacks a number of features that are commonly found on contemporary BASICs, and Texas Instruments later introduced the TI Extended BASIC cartridge that enhanced the functionality accessible to BASIC users. This included a wide variety of features found in other BASICs, as well as new system functions for sprite handling, sound, and other features of the platform.

As was common on home computers, TI BASIC was used not only for programming but also as a thin operating system. On top of Minimal BASIC, TI added commands for text, graphics, and basic file operations like recording to tape or any other file system. Due to the specifics of the TI-99 platform, TI BASIC was most notable for its extremely slow performance, roughly half that of common machines, but conversely sported high numerical accuracy.