Thomson MultiMedia’s Experience with ClioSoft's SOS

John Gyurek, Senior Member, Technical Staff
June 1999
Thomson Consumer Electronics


1. Experience

Overall, SOS has been an easy tool to learn and use. The graphical interface has allowed new team members to transition quickly to the project with a minimum learning curve. Product support has been excellent. The tool has performed as advertised.

2. Why SOS?

We chose to use SOS over the VisualHDL's version control due to our design methodology, which requires a wide variety of files and file formats to be archived. SOS is well equipped to handle such diverse sets of data.

At Thomson Multi Media we chose ClioSoft’s SOS as our revision control methodology for a large MPEG decoder and display processing IC. We wanted something that was easy to use and that would allow the designers to concentrate on design and verification tasks without writing scripts and more importantly without creating a centralized knowledge structure that often emerges using a complicated script based methodology. With most large projects, team members begin to specialize in areas of the design flow that are common to all the designers. Thus projects tend to have, for example, a synthesis expert, a simulation expert, a RCS scripts guy and someone who remembers the phone number of the pizza place that will deliver to the lobby. In general this is beneficial, but in the case of RCS we decided that it was of little value to project to use our resources to maintain the RCS archive. There is also the human nature factor that if something is not easy to understand, it won’t get used. More than a few miscellaneous files and verification testbenches were missing from the archive of the predecessor project because the engineers did not want to hassle with the RCS procedures.

3. Requirements

Besides being easy to use we had additional requirements. We had several environments and a complicated tool flow that the revision control system had to support. The tool flow is shown here with the file types that needed to be archived.

Process Flow

We wanted to be able to have a unified revision control system that would allow us to archive all the file types and provide status to all users. With graphical entry tools the graphics generate code and thus it was deemed beneficial to archive the graphical database as well as the code generated from it.

SOS also improves the efficiency of the team. For example the designers working at high levels of the hierarchy need to know when new versions of low level blocks are ready or have been modified. All they have to do is look at the GUI and check the revision. An icon tells them if their work area is out of date or if they are not using the latest revision. Likewise the synthesis results need to be tied to the graphical database files that generated them for debugging phases. These requirements were satisfied by ClioSoft’s SOS in a way that was intuitive and fast and did not require script writing and maintenance.

4. Process Help

When it became clear that our design capture tool had some complex requirements for revision control, ClioSoft came up with a custom solution in a few weeks by working with the other vendor and delivered a solution that enabled us to keep the design capture database under revision control without having to change methodology in the middle of the project.

5. Features

We have been particularly pleased with the relative ease with which SOS operations can be customized; the tool is extremely flexible and configurable.

6. Quality

It is part of modern ECAD design to spend considerable time on setup and debug of the tool flow. ClioSoft’s SOS product is one of the best ECAD programs we have used in terms of quality and out of the box performance.

7. Support

The support received from ClioSoft has been very good. Even though SOS is easy to use, some questions about customization and use come up from time to time. These were usually answered within 24 hours and the support staff has been knowledgeable and enthusiastic.

The staff at ClioSoft went beyond the expected level of support. ClioSoft designed, in mid-project, a custom solution that enabled us to use SOS with our tool flow in a manner that allowed our design entry tool, exported VHDL, synthesized database and layout database to all be put under a unified revision control system. This was not small task. ClioSoft has to research and understand the database structure of the design entry tool and find an appropriate way to handle it in a revision control environment. They were able to give us a working solution in a few weeks!

8. Summary

The use of ClioSoft’s SOS revision control has been a big help to managing a large project. It has helped in areas of revision control as one would expect but also in improving communications and give designers freedom from the tasks of manual rcs jobs. We plan to use ClioSoft on future projects.