NAME  

TI 99 / 4A

MANUFACTURER  

Texas Instruments

TYPE  

Home Computer

ORIGIN  

U.S.A.

YEAR  

June 1979

END OF PRODUCTION 

1984

BUILT IN LANGUAGE 

TI Basic

KEYBOARD  

QWERTY full-stroke keyboard, 48 keys
2 x SHIFT, CTRL, ALPHA LOCK, FCTN

CPU  

TI TMS 9900 (with 256 bytes 'cache', actually it accesses to 256 bytes of RAM)

SPEED  

3,3 MHz

COPROCESSOR  

TMS 9918A (TMS 9929 in Europe) - Video / Sprite

RAM  

16 KB - Memory expansion card can be added: 4 KB or 32 KB (up to 52 KB)

VRAM  

16 KB

ROM  

26 KB total: 8 KB ROM connected to the CPU + 18 KB ROM in byte-serial bit-mapped circuits (usually known as GROM, Graphic Only Memory)

TEXT MODES 

32 x 24 (16 colors), 40 x 24 (2 colors)

GRAPHIC MODES 

Multicolor mode: 48 x 64 with 16 colors
256 x 192 with 16 colors (only accessed via machine code)
Sprites (only with TI-Extended Basic)

COLORS  

16

SOUND  

3 channels, 5 octaves (110hz to 55khz) and 1 noise channel (periodic and white)

SIZE / WEIGHT 

38 x 25,5 x 6 cm / 2,15 kg

I/O PORTS 

Tape interface, RGB video, Joystick (2), cartridge slot (Solid State Cartridge)

OS  

TI's own system, but a p-code card could be added, which gave access to the UCSD p-system and a Pascal compiler.

POWER SUPPLY 

Special TI external PSU
(pins 1,2: 16v / 1,6A -- pins 2,4: 8v / 0,15A)

PRICE  

ё99 (UK, 1983)

 

TI-99/4a

TI 99 / 4A

The Texas Instrument TI 99/4A was a very successful computer. A large number of ROM cartridges (36 KB each) were developed for this computer, as the popular Extended Basic.

Up to seven peripherals could be connected: 32 KB RAM extension, RS232c, Disk controller (90 KB per disk, up to 3 disk-drives), speech synthesizer, and etc.