Utilizing SuperH Devices to Produce Enhanced Standard-model Engine Control ECUs, beginning in the Early Stages of Engine Development

Hitachi's Automotive Systems has also introduced model-based development for the software used to implement ever-more-complex control systems. "Faced with shorter development times and more advanced control techniques, we decided to replace our past development methodology with methods that use model-based development, thereby improving reliability and productivity," Mr. Ohkubo said.

The Renesas microcomputers that the Automotive Systems currently uses in its ECUs include the Renesas SH7055 and SH7058. Both of these devices use the SH-2 CPU core. "The internal flash memory capacity, CPU performance, and other specifications of these devices cover our entire product range and we have been using these microcomputers for many years. The SuperH microcomputers keep power consumption low while delivering high performance, and they are easy to use in areas like power supply design and circuit board layout. For instance, their high tolerance for noise eases the design of circuit boards," noted Mr. Sasaki.

Recently Hitachi Ltd. has started to use microcomputers with the enhanced SH-2A core to boost the ECU performance even further. Additionally, the Automotive Systems is taking advantage of on-chip peripheral functions that can be used to reduce the processing load on the CPU, freeing up clock cycles for executing control functions.

With software development projects becoming progressively larger, the Hitachi engineers are impressed by the reliability of the Renesas compilers and development systems being offered. "The optimized compilers for the SuperH family and the direct access we have to technical support are among Renesas' strengths as a semiconductor manufacturer. We value the expert the technical assistance we can obtain when we are introducing new compilers or developing diagnostics for microcomputer functions. The level of support that Renesas delivers has earned it a high level of trust not only from the Automotive Systems, but also from car makers," said Mr. Ohkubo.

The people at Hitachi Ltd. have reported that they would like to continue the intensive exchanges of information with Renesas. For example, they want to continue to discuss their requirements for functions and other specifications, and be involved in the development of new microcomputers suitable for use in ECUs. For the future, the engineers at the Automotive Systems are investigating the adoption of dual-core architectures to achieve higher performance. In terms of reliability improvement, they have high expectations that more progress will be made on the Renesas "zero defect" campaign for microcomputers, surpassing past performance.