ti-99/4a dds
Entry screen

TI-99/4A Software

This page contains source code and corresponding screen dumps for programs I wrote in BASIC for the Texas Instruments TI-99/4A computer in 1982 and 1983.


Chess-playing programs for two players.
Screen dump

Screen dump
Source code: CHESS.BAS


Chart a biorythm graph.
Screen dump
Source code: BIORYTHM.BAS

Red Giants White Dwarfs

The TI-994/A was used for displaying the computer-generated screens of the first Greek TV programme to use computer graphics: "Kokkinoi Gigantes Asproi Nanoi". Its speech synthesizer was also used, adding a dramatic effect to the game.
Screen dump credits
Source code: KOKAS.BAS, first prototype: DOK.BAS, second prototype: DOK2.BAS.
Watch the TV show on YouTube.


Painting program; Mac Paint was still some years away.
Screen dump
Source code: PAINTER.BAS

Greek Fonts

The obligatory Greek font. Since the computer had only a character set with 96 characters only a few uppercase characters were reprogrammed. Source code: GREEK.BAS. Another approach was to reprogram all lowercase characters to a Greek font. Source code: SPEKGREK.BAS.


A program to ask chemistry questions (valence values). Not quite eLearning. I guess I was just trying to avoid actually styding chemistry; programming was far more exciting.
Screen dump
Source code: CHEMISTRY.BAS

Speaking Demo

The TI-99/4A featured a speech synthesizer based on linear predictive coding and a three channel sound synthesizer. I wrote a small talking demo program to demonstrate its capabilites. People would crowd around its screen at exhibitions and fairs.
Screen dump
Source code: SPEAK.BAS

High Resolution Graphics

The bit addressable mode of the TI-994A TMS-9918 (US/NTSC) TMS-9929 (Europe/PAL) graphics processor was not available in Basic. This was a serious drawback since other computers such as the ZX-Spectrum and the BBC offered this capability. I wrote the following program in a lame attempt to demonstrate that reprogramming the character generator was just as effective. Source code: HIRES.BAS

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Last modified: 2001-11-17