The ITRON subproject is without a doubt the most successful subproject of the of the TRON Project. Not only did the subproject produce the specification for the world's most widely used real-time operating system (RTOS), it also saved electrical appliance and electronics manufacturers billions of dollars that would have had to have been paid in royalties for licensing commercial RTOSs. That is not to say that there were no implementations of ITRON that were not sold commercially--there were, and people and companies made money from selling them. It is to say, however, that just about every major electronics corporation in Japan was able to develop its own RTOS based on an open specification, and that those RTOSs were incorporated into just about every computerized device that you can think of. This success was a result of the fact that ITRON appeared in the right place, at the right time, and in the right form to produce the de facto RTOS for machine control, just as Prof. Ken Sakamura had planned.
There are people who believe that because NEC Corporation was in an alliance with Microsoft Corporation in the field of personal computers, the company was opposed to the TRON Project, completely and totally. In fact, it was highly interested in the ITRON-specification real-time operating system, and one of its employees, Hiroshi Monden, was actually the chair of the committee that drew up the first ITRON specifications at the TRON Association. On top of that, NEC developed and put on sale one of the first implementations of the ITRON-specification, RX116. In a paper presented at the the Third TRON Project Symposium in 1987, Monden, along with coauthors with Tamotsu Iwasaki and Satoshi Fukui, announced that RX116 had already been adopted by 100 customers in the two years that RX116 had been on sale. Moreover, in 2003, Monden appeared in the 11th episode of "Project X: The Challengers," which looked into the successes and failures of the TRON Project, plus the U.S. government's attempts to derail it, including the BTRON-based educational computer developed by Matsushita Electric Industrial Co..
One thing to keep in mind about TRON specifications is that they are drawn up in non-profit organizations in which there are different membership levels. The members at the highest level, usually major corporations that can spare personnel to attend working group meetings and do research, are the ones that actually draw up the various specifications under the supervision of the project leader. The lower ranking members get to look at the specifications and/or source code first, normally a year or so before they are finally released to the public. This was the case at the TRON Association, which was in existence from 1988 to 2010, and this is the case at the T-Engine Forum, which came into existence in 2002 as the successor to the TRON Association to develop and promote hardware and software standards that are slightly different than those of the original TRON Project, but aimed at the same goals.
Another thing to keep in mind about TRON RTOS specifications is that they are developed to cover a wide range of processors, and thus they include subsets and supersets of functions. In the case of ITRON, a subset called µITRON was developed to run on 8-bit and 16-bit microprocessors. In the case of BTRON and CTRON also, µBTRON and µCTRON were created for low performance equipment use. And this system of developing subsets and supersets of functions has been carried on right into the T-Engine project, where a subset of T-Kernel called µT-Kernel has been specified. T-Kernel is a single source, open specification RTOS that runs on top of the open specification T-Engine development board family.
Toshiba Corporation also produced a leader in the ITRON subproject, Kiichiro Tamaru, who, like Monden mentioned above, served as a committee chair when drawing up the ITRON specifications at the TRON Association. In 1991, at the Eighth TRON Project Symposium, he described his company's µITRON-specification kernel, TR-2. He would go on to speak at many more TRON Project symposia, which is not to mention other events related to embedded systems. At one TRON symposium, he recalled how incredible it was that Prof. Sakamura wanted to standardize and build everything from tiny electronic components, such as microprocessors, all the way up to tall buildings. Actually, there were plans to build a computerized TRON city out in Chiba Prefecture, but they had to be abandoned when the bubble economy came to an abrupt end in 1990. Today, instead of building a completely new city, sections of existing cities, such as Ginza in Tokyo, are being fitted with TRON technologies.
Two other major companies that had personnel on the standards committee, Fujitsu Ltd. and Hitachi Ltd., also produced their own ITRON-specification RTOSs, although they had different types of businesses. Fujitsu, whose efforts were described in 1987 by Akira Shimohara, was famous for mainframe computers, but needed a RTOS to support its electronic components business. Hitachi, on the other hand, was into all sorts of business areas, including home appliances for consumers, so its RTOS would be incorporated into products bearing its name. The people leading Hitachi's efforts in this area were Hiroshi Takeyama, Tsuyoshi Shimizu, and Ken-ichi Horikoshi. Fujitsu concentrated its initial efforts on the Intel 80286 microprocessor, while Hitachi went with the Motorola 68000 series of microprocessors for its initial implementation.
Mitsubishi Electric Corporation is part of a huge industrial group that manufactures all sorts of products, both for industry and consumers, thus putting it in a position similar to that of Hitachi, i.e., needing a high-performance RTOS for machine control. As a result, the company became deeply involved in the ITRON subproject from the outset, and its researchers presented some of the first papers on the implementation of the ITRON specifications. At the Fifth TRON Project symposium in 1988, for example, Kiyoshi Nakata, Hideo Tsubota, Toru Shimizu, Kazunori Saitoh, and Tatsuya Enomoto presented a paper on their firm's implementation of the µITRON specification for Mitsubishi's MELPS7700 series 16-bit microcontroller, i.e., a single-chip computer containing RAM and ROM memory, in addition to timers and serial input/output connections.
Another mistaken belief people have about the TRON Project is that it was set up solely to shut foreign hardware and software vendors out of the Japanese hardware and software markets. In fact, the reverse was true. Some powerful foreign hardware and software vendors wanted to keep Japan from producing its own microprocessors and operating systems, and, as a result, they petitioned the U.S. government to attack the TRON Project, which it did via the Office of the United States Trade Representative. However, in spite all the anti-TRON Project propaganda flying around, the TRON Project demonstrated its openness by inviting foreign companies to give presentations at TRON Project symposia. Under the category of ITRON, two types of foreign firms gave presentations: those with non-TRON products, and those with TRON-compatible products.
James Ready, who created the proprietary VRTX RTOS, is a great example of the TRON Project's openness. Although he never developed a TRON-specification product, he was invited to speak at the fifth and sixth TRON Project symposia, in 1988 and 1989 respectively, as a representative of Ready Systems Corporation. Later, after he got involved with efforts to attempt to turn the Linux kernel into a real-time kernel and had started a new corporation called MontaVista Software, Inc., he was invited to speak at TRON Show 2004 in December 2003. Moreover, even the chief competitor to Ready Systems, Wind River Systems, Inc., which produced the VxWorks RTOS, was allowed to give a presentation and display its products at a TRON Project symposium. That happened at the Eight TRON Project Symposium, which took place in 1991.
The greatest demonstration of openness on the part of the TRON Project was accepting Microsoft Corporation's request to join the T-Engine Forum and give presentations. None other than Susumu "Sam" Furukawa, who was with Microsoft from the time it started developing MS-DOS, gave a presentation at TRON Show 2004 in December 2003. He demonstrated a version of MS Windows running on top of T-Kernel, which gave it better real-time performance, but nothing much seems to have come from it. Several years later, CORE Corporation ported Microsoft's .NET Micro Framework to T-Kernel to enable Microsoft developers to get involved in embedded systems development. This allows developers to use a Microsoft's Windows interface and .NET applications on top of T-Kernel, and it has generated more interest than MS Windows on T-Kernel.
The TRON Project originally began as an "open architecture" project, but later moved in the direction of the "open source" model of development. As a result, although a lot of people do not know about it, the TRON Project has produced multiple open source operating systems that were distributed under licensing arrangements similar to the FreeBSD license. The project has released in open source form a µITRON3-specification RTOS (ItIs), a µITRON4-specification RTOS (TOPPERS JSP), a µCTRON-specification kernel, and a µT-Kernel and multiple T-Kernel-specification RTOSs. One of the driving forces behind behind the first two was Hiroaki Takada, who studied under Prof. Ken Sakamura at the University of Tokyo, and is now a university professor in Nagoya. He was given the nickname of "Dr. ITRON" by the Japanese press.
There might be some people who are wondering why Microsoft decided to join the TRON Project late in the game. Actually, there are a lot of people inside the TRON Project who ask themselves the same question. One reason might be that Microsoft had already joined the TRON Project in the form of a former employee, one Ryu Koriyama, who founded Aplix Corporation and scored a great success with Java on ITRON, which came to be called JTRON. The resulting commercial product, Aplix's JBlend, has been adopted by over a dozen cell-phone manufacturers, and it is also available for those would like to use it on top of T-Engine. It should come as no surprise, then, that Aplix has become a top level member and staunch supporter of the T-Engine Forum. If Hiroaki Takada is Dr. ITRON, then Ryu Koriyama should probably be called "Mr. JTRON."