SoCs For Safer Cars

Renesas electronics has been developing a specialized automotive electronics business and recently rolled out an LSI (large-scale integration) management system including LSI, R-Car (an SoC for next-gen entertainment) and V2H (vehicle-to-home) for ADAS (Advance Driving Assist System) systems. These management systems have higher management functionality than traditional systems.

Figure 1. Renesas’ Ryuji Ohmura.

Renesas had been promoting the value of kit solutions and platform solutions from traditional device sales. In fact, Ryuji Ohmura, Renesas Electronics management director and first solution division director, clearly stated the significance of that approach. A kit solution provides customers’ recommendations about semiconductor products such as Micon http://am.renesas.com/company_info/carrally/index.jsp, analog and power.

A platform solution indicates a business assists customers with the system they would like to make by using an ecosystem. This can include third-party products if the products have a superior system. The R-Car project, for example has more than 130 partner companies.

Renesas recently announced the R-Car VH2, which is much closer to a platform solution than the R-Car H2 chip announced last year (Reference material 1), and use of chip is more clearly specified. R-Car H2 is a higher-end SoC, but Renesas simply used it to show the consolidated concept and its intention to focus on automobile business. R-Car VH2 uses Green Hills Software’s Integrity real-time OS and software development environment (Figure 2). On top of Integrity, Green Hills assists user software development by providing board support packages, middleware (required for the board development tool) and a compile/debugger tool called MULTI. This chip is a result of the collaboration with Green Hills, but software development can be carried out by other third parties.

Figure 2. Solution structure including software GHS = Green Hills Software Ltd. Source: Renesas Electronics

Some of the reasons why Renesas chose Green Hills as a software development tool include:

• Reputation for multicore CPU software development;
• RTOS Integrity uses a reliable and safe architecture, which is an essential component for automobiles;
• Approved by tier-one suppliers for ISO26262 compliance.

The company’s MULTI also has a high core efficiency and impressive debug function. This can reduce the cost and development time. Shortening software development time has huge benefits for Renesas.

R-Car H2 uses quad cores, integrating four ARM Cortex-A15s and Cortex-A7s, to create a high-end architecture that lowers power consumption by Big.LITTLE architecture. The first iteration included a dual-core A15. It did not use a big.LITTLE architecture as the A15 dual-core is the only CPU.

R-Car V2H is equipped with a core that processes the image from up to six cameras and uses the image base to recognize nearby pedestrians or motorbikes while driving. Traditional surround view monitors use four cameras to compose an image and a fixed view (Looking from top of the car). With a new R-Car V2H chip, the angles of the view can be set by the user. For example, it can recognize pedestrians or motorbikes while driving behind a car. This view is useful in Taiwan or South East Asia, where motorbikes often speed around cars.

As for the technical aspects, it simultaneously processes viewpoint conversion, image recognition, image composition, and graphics. It integrates a Car Ethernet AVB interface for car image processing, in addition to IMR for distortion correction, IP to convert four fish-angle images (160 degrees) to rectangular coordinates, Independently, a developed image recognition circuit (IMP-X4), H.264 for image extraction, and Imagination Technologies’ Graphic IP (Powervr-SGX531) for draw Motion JPEG codec graphics. The image recognition library provided by IMP-X4 expands to support a version for basic OpenCV.

A demonstration was done using four digital cameras, each of which has an LVDS interface as a camera with built-in Ethernet AVB, which is not commercially available yet. HD images (1280 x 800) from four cameras were composed into one in real-time. All four simultaneously recognized pedestrians and motorbikes. The reason for installing Ethernet AVD in this chip is its light weight due to a twisted pair circuit harness and its expansion ability for system network control in the near future.

Reference material: Full of future car technology, SoC for Cars.