TLD Systems, Ltd. was an American software company active in the 1980s and 1990s and based in

Torrance, California Torrance is a city in the Los Angeles metropolitan area located in Los Angeles County, California, Los Angeles County, California, United States. The city is part of what is known as the South Bay (Los Angeles County), South Bay region of the m ...

, that specialized in language compilers for the JOVIAL and Ada programming languages that were targeted to

embedded system An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' as ...

s. TLD was founded by Terry L. Dunbar in 1982 and carried his initials. It was based on work on JOVIAL compilers he did at

Computer Sciences Corporation Computer Sciences Corporation (CSC) was an American multinational corporation that provided information technology (IT) services and professional services. On April 3, 2017, it merged with the Enterprise Services line of business of HP Ente ...

and Software Engineering Associates, Inc. in the 1970s. Over the years TLD developed a reputation for experience with, and in-depth knowledge of, both the JOVIAL language and the MIL-STD-1750A architecture that was popular for U.S. Air Force projects. TLD hosted its JOVIAL cross-compiler, and several associated tools such as an assembler, linker, simulator, and

symbolic debugger A debugger or debugging tool is a computer program used to test and debug other programs (the "target" program). The main use of a debugger is to run the target program under controlled conditions that permit the programmer to track its executi ...

, on several platforms including

VAX VAX (an acronym for Virtual Address eXtension) is a series of computers featuring a 32-bit instruction set architecture (ISA) and virtual memory that was developed and sold by Digital Equipment Corporation (DEC) in the late 20th century. The VA ...

VMS #REDIRECT VMS {{redirect category shell, {{R from other capitalisation{{R from ambiguous page ...

and later

Sun SPARC SPARC (Scalable Processor Architecture) is a reduced instruction set computer (RISC) instruction set architecture originally developed by Sun Microsystems. Its design was strongly influenced by the experimental Berkeley RISC system developed in ...

SunOS SunOS is a Unix-branded operating system developed by Sun Microsystems for their workstation and server computer systems. The ''SunOS'' name is usually only used to refer to versions 1.0 to 4.1.4, which were based on BSD, while versions 5.0 and l ...

. TLD then entered the new market for the Ada programming language, which the U.S. Department of Defense had designated as the successor to JOVIAL and other special-purpose languages in use by the military. TLD made embedded system Ada cross compilers targeting the MIL-STD-1750A, hosted on VAX/VMS as well as several Unix-based platforms. The Ada compilers shared the same associated tools as the JOVIAL product. TLD also made a native Ada compiler for the Data General MV/32 20000 under AOS/VS II. The Ada software environment was originally thought to be a promising market, with a number of small, new companies seeking to gain a foothold in it. But the Ada compiler business proved to be a difficult one to be in; many of the advantages of the language for general-purpose programming were not seen as such by the general software engineering community or by educators. TLD Systems was still actively marketing its Ada and JOVIAL products up through 1995. Faced with the need to conform to the new

Ada 95 Ada is a structured, statically typed, imperative, and object-oriented high-level programming language, extended from Pascal and other languages. It has built-in language support for '' design by contract'' (DbC), extremely strong typing, exp ...

standard for the language, in late 1995 TLD announced a joint arrangement with Ada Core Technologies in which that firm's Ada technology would be adapted to work with TLD's other cross-development tools. TLD Systems ceased doing business as such in 1998. Following that a small consulting firm named TLDworks, Inc. came into being with an address in Hermosa Beach, California.

References

{{reflist, 2 Software companies established in 1982 Companies disestablished in 1998 Software companies based in California Defunct software companies of the United States Companies based in Torrance, California Ada (programming language) 1982 establishments in California