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:
This home page is maintained by David Pitts.
Please email [email protected]
with comments and corrections.
Last modified 2005/04/05.