Dassault AT
"We selected a modular, multitasking architecture that would allow us to differentiate from the competition, give us exceptional flexibility for development, and permit us to evolve rapidly. The simplest way was to utilize a real-time kernel that would play the role of the leader with respect to the totality of the tasks," explained Claude Rousselot, Digital Television Product Manager at Dassault AT. "Based on our experience, we didn't want to use a proprietary kernel. We were also concerned with the cost of run-time fees due to our high volume production. Finally, we wanted to control the kernel because of real-time constraints that allowed us to modify it." --Claude Rousselot, Digital Television Product Manager at Dassault AT
DASSAULT AT incorporates the Mentor Graphics' Nucleus PLUS Real-time kernel in their Canal+ set-top boxes
Dassault AT and the digital TV
Dassault Automatismes & Tèlècommunications (Dassault AT) is a subsidiary of what is now the new Thomson-CSF Detexis entity since January 1, 1999, which includes Dassault Electronique, Thomson-CSF Radars & Contre-Mesures, and Thomson-CSF Missiles Electronics. Apart from their well known activities in the area of electronics transactions (cash dispensers, credit card and smart card applications...) and telecommunications (telephones, telephone line testing systems, routers, communications boards...), Dassault AT has been developing a multimedia project since 1995. The project first started with the manufacturing of analog decoders for Canal + (SYSTER), then evolved towards digital TV from an MPEG 2 decompression board for micro-computers with a PCI bus, which had been developed in-house.
In early 1997, Dassault AT decided to invest in the development of a digital set-top box for Canal +. This product, which was validated by Canal + in October 1998, was immediately placed into production. The digital set-top box was originally intended for sale through distributors, which started in Italy and the Netherlands under the Nokia brand name, and by several other resellers in Europe, including SIM2 (subsidiary of Italtel) and Strong, a company based in the UK. The planned volume of production reaches 300,000 to 400,000 units per year.
Technology choices oriented towards performance and scalability
The basic idea was to develop a highly evolved set-top box with a superior performance compared to existing products, which would operate faster and be far more technologically advanced than the competition, by implementing the PCI MPEG2 board developed around LSI Logic components. The LSI Logic components naturally meant the selection of a 54 MHz, 32-bit R3000 compatible MIPS processor for the development of the digital set-top box application.
The next problem was a decision regarding the real-time kernel. "We selected a modular, multitasking architecture that would allow us to differentiate from the competition, give us exceptional flexibility for development, and permit us to evolve rapidly. The simplest way was to utilize a real-time kernel that would play the role of the leader with respect to the totality of the tasks," explained Claude Rousselot, Digital Television Product Manager at Dassault AT. "Based on our experience, we didn't want to use a proprietary kernel. We were also concerned with the cost of run-time fees due to our high volume production. Finally, we wanted to control the kernel because of real-time constraints that allowed us to modify it."
Mentor Graphics' Nucleus PLUS real-time kernel, sold with source code and without royalty fees, met all of these requirements. Mentor also performed the work for the portation to the MIPS processor. "We were then able to implement Nucleus PLUS without difficulties," said Didier Bonnerot, the project leader. "According to what we expected, we were able to modify the kernel without any problems. The product works, it's reliable and perfectly suits our needs."