First automotive dual core, floating point MCUs from Texas Instruments let designers innovate and differentiate for safety critical applications

“According to Strategy Analytics, the number of microcontrollers per car is forecast to double by 2012,” said Wayne Lyons, Director, Embedded Solutions, ARM. “Added to this growth, the sophistication of safety control functions is expected to increase substantially. TI’s Cortex-R4F processor-based TMS570F MCUs offer designers a way to reduce that complexity while offering top-notch performance and the ability to differentiate their solutions.”



Floating point adds precision and differentiation, speeds time-to-market



The TMS570F MCU is the industry’s first dual core Cortex-R4F processor-based floating-point MCU, and allows automotive system designers to implement both single and double precision floating point math depending on performance requirements. Accelerated multiply, divide and square root functions enable physical model-based control through development environments like The Mathworks Real Time Workshop™ and ETAS ASCET™. These graphical-based environments help engineers accelerate complex safety application designs and add differentiation through custom vehicle control algorithms for unique handling, ride and user experience. As the demand for differentiated, safety-critical automotive applications increases, MCU-based systems that can meet these performance demands via integrated, intelligent systems will become increasingly important.



“Embedded control will continue to be a primary driver of high-end automotive microcontroller performance and functional development,” said Mark Fitzgerald, senior analyst with Strategy Analytics. “However, going forward, multi-sensor advanced driver assistance system applications will increasingly emerge as high performance processor drivers. As a result, multi-core designs will increase for greater computational performance.”



Developers typically begin creating algorithms in a floating point environment for validation, and then convert the code to run on fixed-point devices. Using the TMS570F MCU, however, developers can now eliminate the weeks – and often months – of time spent contending with scaling, saturation and adjustment of numerical resolution required in fixed point implementations. The dual core lockstep implementation also simplifies software development by removing redundant safety system requirements.



Safety designed from the ground up



Hardware built in self test (BIST) of both memory and CPU functions further increases integration and lets designers detect latent defects without using complex safety software drivers that reduce performance and have significant code size overhead. Hardware comparison of the CPU’s outputs provides on line diagnostics with exceptional safety response time and no additional software overhead.



The Cortex-R4F processor-based MCU is designed to meet error-free automotive safety standards and provide system-wide protection through seamless support for error detection from the processor, through the interconnect and into the memories. The error correction code (ECC) logic is integrated into the Cortex-R4F CPU, which protects both the memories and busses. Because ECC is evaluated within the CPU, the system takes advantage of the eight-stage pipeline to allow time for ECC evaluation with no performance impact. In the event of a memory error, the ECC logic will correct it, rather than just communicating the error and stopping the system.



“As a leading consultancy for functional safety, Exida Consulting worked closely with TI and performed a detailed review of their development processes and conducted a reliability analysis, founding that the TMS570PSFC66 device meets all of the relevant SIL 3 requirements of IEC 61508,” said Bill Goble, CEO, Exida Consulting LLC. “This partnership has enabled TI to further enhance their knowledge of IEC 61508 safety requirements and has allowed Exida to extend their safety expertise to the development of complex multi-core processors for automotive safety applications.”



ARM at the heart of TMS570F MCUs

The TMS570F MCU platform uses two identical ARM Cortex-R4F processors combined with an initial two Mbytes of on-chip flash memory. Industry standard peripherals include FlexRay™ protocol controller, up to three CAN and two LIN modules along with TI’s high-end timer co-processor and two 12-bit analog to digital converters (ADC). Targeted applications include chassis control, braking, electronic vehicle stability and steering as well as advanced driver assistance with higher and lower memory and performance variations in development.



Broadening portfolio of innovation and leadership in automotive applications

TI processors have a history of leadership and innovation in the automotive industry. TI's ARM processor-based TMS470 MCU, for example, is used in the majority of automotive safety systems around the world such as antilock braking systems, electronic stability control systems and airbag electronics, while TI’s leading digital signal processors (DSP) offer innovative solutions for infotainment, navigation, and vision- and radar-based driver assist systems. The TI automotive portfolio also extends into mixed signal solutions, integrating analog-, power-, digital-circuits.