Texas Instruments TI-99/4A

Resources

Wiki
oldcomputer.info (pinouts)
99er.net
Robots & Computers (pinouts)
TI Game Shelf (game disk and tape images)

Documents

[doc_library doc_category=”ti” status=”publish” search_box=”false”]

Internals

Motherboard

Power adapter board

Keyboard

Reassembly

Loading games

Unlike almost all other machines, this one needs a special “Assembler/Editor” cartridge in order to load non-basic programs. There seems to be no workaround for that.

For basic programs, the command to load it from the tape is (again, unlike anywhere else):

  • OLD CS1

And it won’t work if you enter cs1 in non-capital letters.

It is fairly easy to attach this machine to a PC and replay programs from wav audio files. Pins 8 and 9 on the back joystick-like port need to be connected to an audio jack going to the PC. Pin 9 (bottom row, rightmost) to the ground and pin 8 to the audio signal.

In order to convert images to audio files, please follow instructions from the oldcomputer.info page in “Preparing tapes” paragraph.

Discover more from Old Crap Vintage Computing

Subscribe now to keep reading and get access to the full archive.

Continue reading