TI-99/4A

Home Computer TI-99/4A

Audio Guide

Home Computer TI-99/4A  Enhanced version of the TI-99/4 model marketed at the end of 1979, it was placed on the market starting from June 1981, had a certain diffusion especially in the USA but due to the commercial war with Commodore International it was unable to achieve a significant number of sales, especially due to the success of the Commodore 64, and production ceased just two years after launch. It supports lowercase writing, unlike some machines of the time which required specific expansion, and a full-travel keyboard, and is based on the TMS-9900, a 16-bit CPU clocked at 3 MHz. The graphics are 16 colors with a video resolution of 256 x 192 pixels, organized in 32 columns x 24 rows, with characters (ASCII or user definable) based on 8 x 8 pixels.
Built around a single block, which contains the CPU, the motherboard and the cartridge slot (SSC Solid State Cartridge), it also had a 5.25" floppy disk drive, a serial card, among other options. RS-232 equipped with two serial ports and one parallel, a P-Code card for supporting the Pascal programming language, a thermal printer, an acoustic coupler, tape drives for saving and loading data (on normal cassettes), a pair of joysticks and a 32 kB memory expansion. The peculiarity of the machine was that it was sold already equipped with a monitor (a modified version of a 13" Zenith Color TV), as the RF adapter for connection to a normal TV it never obtained certification from the Federal Communications Commission. In Italy it was sold without a monitor and the video output was fully compatible with normal televisions. Another peculiarity for the time was the presence of an optional speech synthesizer, exactly like the one present in the Atari 2600, which allowed the software or games to be equipped with speech synthesis. The synthesizer was provided free of charge to customers after the purchase of a certain number of cartridges, and was widely used in several video games written by TI itself.

Wikipedia TI-99/4A

           TI99-4A    Main BOARD
Released:June 1981 Price: US$525 (without monitor) How many:2.8 Million
CPU:TI TMS9900, 3MHz Memory:16K RAM, 26K ROM Sound: 3: channels + effect Joystick: 2
Display:Video via an RF modulator 32 characters by 24 lines text 192 X 256, 16 color graphics
Ports:ROM cartridge (on front) Data storage cassette Audio/Video output Joystick input CPU bus expansion
Peripherals:Speech Synthesizer Peripheral Expansion Box Data storage cassette 300 baud modem
OS:ROM BASIC