Jaguar's high speed program

A custom software tool being created for Jaguar will enable the luxury car manufacturer to cut several weeks from a typical development project

The MathWorks has won a substantial order from Jaguar Cars for a consultancy project to deliver a customised software tool for automatic code generation. The aim is to produce code for use with 32-bit microcontrollers in interface boxes installed on development vehicles, in order to convert between the CAN and J1850 message protocols.

As a result, the timescale of Jaguar's development programmes are likely to be reduced significantly, while direct financial savings will also result.

Over the eight month period of the contract, a team of three consultants from The MathWorks will develop the code generation tools, which will mainly be used by Jaguar's Multiplex team for work on the prototypes for new Jaguar vehicles. Suitable hardware for the interface box will be developed elsewhere in parallel with this work, and the two groups of consultants will liaise closely on the project.

Customised tools

Rather than create the code generation tools from scratch, The MathWorks will be customising tools that are already available within its existing Real-Time Workshop and Stateflow Coder software products. The company has undertaken similar consultancy projects in the past to create customised code generation tools for use with other protocols and hardware platforms, but this is believed to be the first time that such a system has been based around CAN, J1850, and the Motorola MPC555 microcontroller. CAN (Controller Area Network) is the protocol most commonly used with the powertrain network of a motor vehicle, while J1850 tends to be used for less demanding applications, such as components that make up the body network - the air conditioning module, door modules, rear window demister module and the myriad of smaller electronic modules located around the body of the vehicle.

Data conversion

Although it is already possible to convert data between CAN and J1850 formats using commercial off-the-shelf products, this generally involves combining different hardware and software and customising the final solution - an approach that is extremely expensive and time-consuming. The current consultancy project will result in a system that is not only immediately available, but is also far less expensive, making it possible to use it concurrently in an entire fleet of vehicles.

The new automatic tools will generate code that can be downloaded to the Motorola MPC555 32-bit microcontroller installed within the interface boxes. In addition to the protocol conversion facility for creating the links between existing and additional developmental control modules on-board vehicles, the interface boxes will also handle analogue and digital I/0 as necessary for communicating with individual sensors and actuators.

Up to now, it has usually been necessary to write custom software for the interface boxes used in each installation. Not only is this time-consuming, but it runs the risk of errors creeping in. The work has often been sub-contracted to external code writers, although more recently Jaguar's own staff have been using a suite of validation tools as part of a thorough verification process..

In-house validation

Automatic code generation will mean that all work can now be completed and validated in-house. The engineers will be able to assemble function block diagrams quickly and the software will then create the code from these. Over a five-year period, this is expected to save many man-weeks of verification time in each project, as well as eliminating the direct cost of sub-contracting the coding work. In addition, it is anticipated that the quality of the code will also improve.

Jaguar's management expects the main benefit to be a reduction in development time. Several weeks will be cut from a typical development project, partly through the reduced verification effort and partly through the increased use of economical interface boxes that will allow the simultaneous trial of more prototype control modules across a larger fleet of vehicles.

Patrick Penon, who is handling the project at Jaguar, says: "We easily justified this project in terms of the amount of manpower that we would be saving."

The MathWorks
f107@industrialnetworking.co.uk