# TI 990 Page

Welcome to Dave Pitts' TI 990 web page. The above picture is my Texas Instruments (TI) 990/4 system that I have at home. I also have a TI-990/10 system with 256K of memory, DS10 disk and 911 VDT. I worked on the TI-990 from its inception, wire wrapped boards in a TI-960 chassis, until 1980. The first 990 was the 990/9 in 1973 and was built for a large Motel chain reservation system. I worked on the cross development environment for the Motel that ran on their PDP-10 and was written in ALGOL. The 990/9 was superceeded by the 990/10 and became commercialized with memory mapping and high speed disks on the TILINE (kind of like DEC's UNIBUS). The 990/4 came out with the advent of the TMS-9900 chip in 1976. The 990/4 was superceeded by the 990/5 (added the TILINE, more memory and three on board serial ports). The 990/12 was added to the product line and added hardware floating point, writeable control store and some other "goodies". I wrote and collaborated on parts of the Operating Systems (TX990 and DX10) and various utility programs, editors, compilers, assemblers and linkers.

In seeing some of the retro-computing effort on behalf of the TI 990 I've got some links that may be of interest:

- asm990 - A Cross Assembler for the TI 990. It is written in 'C' and runs on Linux. Version 1.3.0: Many improvements including conditional assembly, revamped expression parser (now supports logical expressions) and 990/12 support.

- lnk990 - A Cross Linker for the TI 990. It is written in 'C' and runs on Linux. Version 1.1.2: Cleanup and miscellaneous fixes.

- sim990 - A TI 990 simulator. Version 1.4.3: It implements the TMS-9900 and TI-990/10 instructions with interrupts and it can boot TX990, DOCS and DX10. Supported devices: Serial terminal, Serial printer, Card Reader, FD800 floppy disks, 911 VDT and TILINE Disk and Tape.

- Utilities - These are utilities that I used to extract the disk and floppy images from my 990 systems, floppy directory list and file reader, generate TILINE disk files and disk data dump.

You will want some "disks" to run with the sim990 program:

- DX10 3.2.3 System This is a DS10 system image. This disk has a preinstalled COBOL compiler and SORT/MERGE.

- DX10 3.3.0 System This is a DS10 system image.

- DX10 3.6.0 System This is a DS50 system image.

- DX10 3.7.0 System This is a WD500 system image.

- DOCS System This is a DS10 system image with the DOCS diagnostics suite.

- TXDS System This system has my command line control program and VT100 CRT DSR. Also, SYSUTL was patched to allow current Y2K years.

- 990 Focal System This image has a bootable FOCAL interpreter.

- 733 ASR TXDS System

- FORTH System - The FD800 FORTH boot image, doesn't require interrupts.

- FORTH data - The FD800 FORTH data image.

This home page is maintained by David Pitts. Please email dpitts@cozx.com with comments and corrections.
Last modified 2005/04/05.