Renesas Rolls Out On-Chip 2D/3D Graphics Engines for Car Navigation

2/26/2004 - Renesas Technology Corp. announced the SH7770 SoC (System on Chip) for high-performance car information systems (CISs) such as next-generation car navigation devices, employing a newly developed SH-4A SuperHTM Family CPU core, and incorporating a new 2D graphics engine developed for map drawing plus a newly developed 3D graphics engine capable of various kinds of drawing processing, together with a GPS baseband processing function and a varied and comprehensive range of on-chip peripheral modules. Sample shipments will begin in May 2004 in Japan.

From the same month, Renesas Technology also plans to offer a reference platform that will enable users to carry out efficient system development.

The SH7770 offers the following features.

  1. High-performance SuperH Family SH-4A CPU core, upward-compatible with SH-4 CPU core
    The SH-4A is a newly developed CPU core with a maximum operating frequency of 400 MHz, approximately 70% faster than the 240 MHz of the current SH-4 CPU core, and offering high processing performance of 720 MIPS. The cache memory employs a 4-way design that provides a higher hit rate and helps speed up software processing. These features make it possible to implement high-performance systems for next-generation products. The instruction set is upward-compatible with that of the SH-4, allowing existing programs to be used and system development time to be shortened.

  2. Newly developed 2D and 3D graphics engines providing high-speed implementation of varied drawing functions
    The 2D graphics engine offers fast and high-quality implementation of the map drawing operations essential to car navigation systems. A bold-line drawing function makes it easy to draw a line of constant width regardless of direction when drawing roads, while an anti-alias*3 function offers smooth drawing of polygons, oblique lines, and so forth. Such processing has previously been executed by software or dedicated LSIs, and providing it in hardware form in a single chip offers both faster processing and a reduction in the number of parts.

    A PowerVR*4 MBX 3D graphics IP from Imagination Technologies, Ltd. (IMG) of the United Kingdom is used as the on-chip 3D graphics engine, enabling the SH7770 to handle not only 3D drawing for navigation purposes, but also multimedia applications requiring high-speed 3D drawing in car information systems. This IP employs a method that keeps external memory accesses to a minimum, greatly reducing the number of accesses and enabling faster drawing to be achieved. Smooth, high-quality 3D graphic display operations can thus be achieved without the use of external dedicated graphics memory.

  3. More than 50 assorted peripheral modules necessary for next-generation in-vehicle information terminals The SH7770 has over 50 on-chip peripheral modules necessary for next-generation car information systems, including a GPS baseband processing module and various sound interfaces and serial interfaces. A bus arbitration circuit is also included that enables external memory accesses by peripheral modules to be performed efficiently according to a preset priority order, and a unified memory architecture that enables memory to be shared among specific modules makes it possible to reduce the number of external memory parts used.

    The SH7770 thus includes most functions necessary for a system in a single chip, making possible single-chip implementation of a high-performance system, and enabling lower system cost to be achieved by reducing component parts.

The recent trend in map display - the main function of a car navigation system - is toward greater speed and versatility, including the clearer and more realistic displays provided by three-dimensional display capability. At the same time, the functions of a car navigation centered car information system are rapidly becoming more diverse, including Internet connectivity via a mobile phone, and acquisition of various kinds of periodically updated information such as weather information, details of local restaurants, and news, in addition to the basic car navigation function.

Further development of the multimedia capabilities of car information systems can be expected in the future, placing correspondingly heavier demands on system developments. Important factors in future system development are likely to be achieving superior functions through the use of intelligible displays and making efficient reuse of previously developed software assets.

To meet these needs Renesas Technology has developed the SH7770, employing an SH-4A CPU core upward-compatible with the SH-4 currently widely used in car navigation applications, and incorporating various peripheral functions essential to car navigation systems, including a GPS baseband processing facility.

The SH-4A CPU core used in the SH7770 features a 400 MHz maximum operating frequency and high processing performance of 720 MIPS. In addition to the approximately 70% increase over the 240 MHz maximum operating speed of the previous SH-4, the SH7770 achieves a higher cache hit rate through the use of 4-way cache memory and this means to help to further speed up software processing. Also, upward-compatibility with the SH-4's instruction set allows the use of programs from a current system employing the SH-4.

The 2D graphics engine includes functions ideally suited to map drawing. A bold-line drawing function suitable for road drawing enables a line of constant width to be drawn regardless of the drawing direction, and makes possible endpoint processing and painting of linked areas. An anti-alias function reduces jaggedness in outline displays of polygonal areas such as parks and schools, enabling smoother outline drawing. Use of a single-chip hardware approach to such processing, instead of the conventional use of software or dedicated LSIs, makes it possible to achieve faster processing and reduce the number of parts. This 2D graphics engine is functionally upward-compatible with current Renesas' Q2SD 2D graphics engine, facilitating efficient development of a system employing the SH7770 by current Q2SD users.

The 3D graphics engine can handle 3D drawing not only for navigation applications, but also for multimedia applications requiring sophisticated, high-speed 3D drawing in car information systems. By processing only the visible area, unlike conventional 3D graphics engines, external memory accesses have been kept to a minimum. This makes it possible to achieve high-speed, high-quality 3D drawing display, in full color and with implementation of anti-alias processing, without the use of external dedicated 3D graphics memory.

To further lighten the CPU load, both graphics engines also include a geometry engine that performs such tasks as vertex coordinate calculation. This processing is executed at a high operating speed of 100 MHz, enabling smooth, high-image-quality 2D/3D graphic display operations to be implemented.

The SH7770 also incorporates a variety of peripheral functions necessary for next-generation car information systems. The more than 50 on-chip peripheral modules include a module for GPS baseband processing, previously handled by a dedicated chip, an interface for connection to a speech processing IC and a USB interface for connection to a mobile phone or the like, an in-vehicle LAN CAN interface, and a variety of serial interfaces.

The memory controller and bus bridge also include bus arbitration circuitry used to set a priority order for bus accesses by the various modules. Four priority levels can be set, enabling external memory to be accessed efficiently by the many internal modules. These priority level settings can be changed by the user in line with priority requirements for CPU and drawing performance. In addition, the use of a unified memory architecture enables memory to be shared among specific modules, making it possible to reduce the number of external memory parts.

The external buses provided are a 64-bit bus for connection to DDR-SDRAM (Double Data Rate-SDRAM) and a 32-bit wide extension bus for connection to flash memory or SRAM. The width of the SDRAM bus can also be made 32 bits.

As described above, the SH7770 incorporates most of the functions needed by a next-generation car information system, enabling a powerful and sophisticated system to be configured using a single chip. This makes it possible to achieve lower system cost by using fewer parts, and also enables overall system power consumption to be reduced.

The package used is a 520-pin BGA (33 mm 33 mm).

An E10A-USB emulator connected to a host PC via a USB interface can be used as a development environment, and the provision of an on-chip debugging function enables real-time debugging to be carried out at the maximum operating frequency.

A user system development reference platform offering the following features is also available, enabling the user to carry out efficient system development.

  1. Includes car information system oriented peripheral circuits, providing a user system actual-device verification environment.
  2. Can be used as a software development tool for application software, etc.
  3. Allows easy addition of original functions by the user.

Renesas Technology will continue to develop models offering higher CPU performance, speed, and functionality, in order to provide products that offer a timely response to evolving market needs.

Typical Applications

SuperH is a trademark of Renesas Technology Corp.

Previous Page | News by Category | News Search

If you found this page useful, bookmark and share it on: