Tegimenta is a 460 person subsidiary of Hoffman La Roche AG. Located in the Diagnostic Systems division, it is dedicated to the development, production, and assembly of high-precision analytical systems used in hospitals and laboratories to perform in vitro diagnostics. After 24 years in business, Tegimenta's products are used worldwide, with major customers in the USA, Europe and Japan.

The system developed in Ada provides control of the COBASr INTEGRA, an integrated analytical system with throughput of up to 750 tests per hour by use of Absorbency and Fluorescence Photometry and Ion Selective Electrode. The system comprises a user interface, order & result processing and calculation, data storage and retrieval, printing, real time instrument control, scheduling of tests, event tracking, server interface to laboratory information systems (LIS), quality control, system configuration, system maintenance, and system diagnostics.

The application now totals 220,000 lines of code. It has been developed by a ten person team on HP 9000/ series 400 and 700 running under UNIX, over a period of 3 years. Tegimenta engineers used the Alsys development environment, a proprietary GUI builder, and Cadre Teamwork. They followed the Structured Design and Structured Analysis method of Tom DeMarco, using the Real-Time Modeling of Pages Jones to develop the software.

A TCP/IP network supports six client server connections to control the analytical instrument and an RS 232 network provides an interface for LISes. Some bindings to Raima db_VISTA DBMS and some to OSF/MOTIF, as well as proprietary UNIX bindings have been used. "Our system consists of several UNIX processes and Ada tasking is also used," states Martin Burri, Software Project Manager. UNIX message queues are used for Internal Processor Calls. The real time processing takes place on a INTEL 186 processor board.

According to Martin Burri, "Ada was initially chosen because it preserves our knowledge of programming languages like Pascal and Modula 2, it is more reliable than other languages because of the required validation of the compiler, and it proved (after comparisons with C) to provide significant advantages in terms of software engineering." With regard to the Tegimenta compliance with ISO 9001, which provides quality and certification requirements for medical instrument development, the "use of Ada is a key asset," asserts Martin Burri.

During the development, Ada clearly showed the advantages of its strong typing. "Let's say if you have compiled and linked successfully, and something goes wrong, it is 95% a matter of logic and/or design error, but never something like a pointer mismatch," states Mr. Burri. Also, Tegimenta engineers found Ada to be a very easy language to learn and understand, based on their knowledge of Pascal and Modula 2. The engineers were able, therefore, to implement more elaborated features while working with Ada.

"Alsys technology was the only real Ada implementation for HP9000/300 hardware at the time we started," states Mr. Burri. AdaProbe provided significant support during the development; the Alsys environment included rich implementation of Ada Chapter 14 (representation clauses) and supported mixed development and integration of the db_VISTA DBMS.

Convinced that their development’s success is due to the use of Ada and Alsys tools, Tegimenta now plans to use them both in future projects. Tegimenta looks forward to the release of Ada 95 and is especially interested in employing object-oriented programming features with extensible data types, the internationalization of STRINGS, and less restrictive visibility rules.

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