Enabling infotainment-equipment cost structures with open-system architectures

The infotainment systems of original equipment manufacturers (OEMs) recently have been subjected to increasing competition from the retrofitting solutions on the so-called aftermarket, for which there is at present no adequate response. A similar situation has always been the case with car radios, where retrofitted units have long had an obviously better price/performance ratio, not only in the low-price segment but even among very high-quality systems.Are traditional auto microcontrollers being displaced from infotainment units? Automotive suppliers have drawn their conclusions, and now serve not only the established manufacturers, but also to a significant extent, the aftermarket, so as not to lose out to companies in the entertainment electronics industry. On the other hand, the car manufacturers, not wishing to miss out on the lucrative original infotainment business, were obliged to force the development of these systems. There was no way to win the price war over car radios. The quality standard of integrated systems, which the buyer associates directly with the vehicle brand, must be higher out of necessity than is the case with comparable aftermarket units. The manufacturers therefore created the distinguishing feature of stylistic integration in the brand-specific car interior, which aftermarket systems by nature cannot offer. In the premium sector, the media-orientated system transport (MOST) bus – optical-fiber cabling previously unknown in the entertainment-electronics area – was introduced.

It was also in this premium sector that GPS-supported vehicle navigation was established as a distinguishing feature. It did not, however, take the entertainment-electronics industry long to catch up and be in a position to offer units with astonishing performance for a fraction of the price of integrated systems. Today, even the close meshing with sensors that are integrated in the vehicle can be more or less compensated for by retrofitted units, without having to alter the long-term price relationship.

A closer look at the various infotainment units shows why the automotive supplier industry is losing more and more ground in the sector. Almost without exception, original units work with automotive-specific semiconductor components, whereas entertainment electronics mostly use application-specific standard products (ASSPs). The volume in the market for these ASSPs is many times that of the automotive market, so the per-piece price is significantly lower. But the real problem is not so much the price of the components, because the steady reduction in the diversity of microelectronics means that the hardware portion of the costs is decreasing. The total system price, including the hardware, is made up of the costs of developing the equipment platform and the software, testing the system, and maintaining the platform. The effort of developing and testing the software is rising exponentially with the increasing diversity of functions. To keep these costs under control, the established operating systems on the automotive market have acquired more and more standard infotainment functions, making a whole spectrum of applications available to today’s developer. This, however, makes it increasingly difficult for the software supplier to support automotive-specific processor architectures when these are based on proprietary microcontrollers. Initially, as a rule, the cost of these is borne by the semiconductor companies, which naturally have a lively interest in widespread software support for their microcontrollers. In the final analysis, however, these costs for multiple portability, software maintenance and development do affect the system price, and the car manufacturer, or rather the car buyer, must pay for them.

KEY TO COST REDUCTION

One possible way out of this dilemma would be to dispense with in-house development, restricting it to interfaces to the portable units from the entertainment-electronics sector – the question of infotainment would then no longer be an automotive topic. Another obvious way to resist the pressure of price and functionality from the entertainment electronics sector over the long term is an open, standardized microcontroller architecture, such as that which has long existed in the PC market, where it is advantageous to all involved. There are already signs that the traditional automotive microcontroller will soon be superseded. Every motorist who is interested in an infotainment system already is more or less familiar with the PC, using it to organize music or videos, for communication, or just to surf the Internet. This is precisely the target group for the concept of the Auto PC, which aims to put the home multimedia world on four wheels. The present obstacles to this concept are the excessively high price of processors and the power consumption of the chip sets. But standardization, as the “secret of success,” will prevail here, too, and the ideal architecture for future infotainment systems must thus fulfill the following basic requirements:

• The command set of the processor and the basic architecture must be open and freely available, so that more than one manufacturer can be selected as a supplier. The semiconductors must, of course, meet the stringent requirements of the automotive sector.

• The performance and functionality of the processor must be scalable over a wide range. Both entry-level and premium units must be covered by the processor architecture, so that, in principle, the same software can run on any unit.

• The system architecture must ensure strict separation of vehicle-specific and multimedia-specific data processing, to prevent the infotainment unit from influencing the vehicle characteristics under any circumstances.

In addition, it is also important for the ideal system architecture to fulfill the specific requirements of the car manufacturers and their suppliers:

• For the car buyer, the equipment must be clearly distinguishable from aftermarket products, but at a cost that is not significantly higher. The main differentiating features are scope of functionality and system quality.

• The vehicle manufacturer must be able to achieve the greatest flexibility in the integration of infotainment platforms from different suppliers on the vehicle platform.

• The automotive supplier must give the infotainment platform the greatest possible flexibility, with regard to a wide range of car manufacturers and to the integration of future customer requirements.

• The investment in a platform generation must also be protected, so that hardware cost optimization (such as changing to new types of memory) can be implemented quickly and flexibly.PARAMETERIZED INFOTAINMENT SYSTEM

The new, parameterized infotainment system (PARIS) comes very close to the above ideal. The hardware aspect of PARIS is based on an open microcontroller definition, with, processor cores, periphery interfaces and a number of special function blocks, such as memory or hardware accelerators, integrated on one building block. The difference between this and conventional microcontrollers is that the PARIS architecture is flexible, being based on a modular, “construction-kit” system (Figure 1).

The PARIS construction kit contains all the basic, integration-capable elements needed to create an infotainment system including simple serial interfaces, such as I2S or I2C, as well as complex modules such as CAN, MOST, FireWire, Ethernet, and even FlexRay. These and a complete series of other interfaces are fitted with uniform “building block” or module interfaces, and can thus be connected to an internal bus system. Modules like memory, arithmetic units and complex accelerator blocks for graphics, video, and audio functions are fitted with uniform module interfaces in the same way.

The CPU is also treated as a module. It can control the bus system, or share it with other bus masters. When several masters have to access one system resource, arbitration takes place at the slave connection. This permits lock-free working of several masters on one bus, and thus the operation of several CPUs in one infotainment system.

All modules can be parameterized, that is, the respective function can be specified more precisely in the system definition phase. This means that PARIS is not just a special microcontroller for a specific task, but rather comprises a whole series of microcontroller variants. There being only very few restrictions on the possible combinations, the selection of a specific PARIS variant at the same time defines a product that is tailored specially to the task to be performed.

The PARIS construction-kit principle can be implemented with function modules that are independent of the actual hardware, the silicon chip. Using programmable logic building blocks, the synthesized prototypes are mapped on real hardware, which can be tested in the target systems. Only when the interplay of all functions fulfills the requirements is the final microcontroller created on the production building block, which then costs only a fraction of the FPGA.

Traditional microcontrollers are often developed using FPGAs as a prototyping tool and then converted to ASICs with hardwired hardware. However, the types of ASIC used are much more costly to produce and are in no way identical to FPGAs. The system developer thus completely loses sight of the actual definition of the microcontroller family, and neither the production time nor the long-term availability can be adjusted for individual needs.

The PARIS microcontroller construction kit strengthens the relationship between semiconductor manufacturer and developer, so that the only determining factors in the definition of a product are the interests of its end users. This freedom can be exploited directly:

• Logic, memory, and CPU exactly reflect the required specification

• No development time is lost in adapting to the compromises of traditional microcontrollers

• Hardware accelerators are installed only in the variants in which they are needed

• Hardware/software partitioning optimizes the utilization of the silicon

• Rapid availability of prototypes

• Defined long-term availability

• No risk of competitors copying the system, because the microcontroller variant is not available on the open market

The PARIS open hardware architecture guarantees maximum flexibility, while forming the basis for comprehensive support through application software. The PARIS development system automatically ties the construction-kit modules into the software development environment, creating a uniform layer of hardware abstraction that makes the porting of standard applications very efficient.

A complete kit is available to ease the developer’s entry to the development of PARIS-based infotainment systems. It is delivered with a preconfigured microcontroller, as well as drivers and application software. The kit consists of a base board (Figure 2, left) in DIN-1 rack format and a number of physical interfaces, such as VGA, TFT, IDE, audio, 10/100Base-T Ethernet, RS232, TTL serial, USB, CAN, MOST, FireWire, MMC/SD/SDIO boards, and other GPIO plugs. The base board has a module slot for the processor module and up to two additional extension modules.

The central component of the processor module (Figure 2, right) is an FPGA with several million system gates, 64MB of DDR2 RAM and 16MB of flash memory. All physical interfaces are connected directly to the FPGA, thus allowing almost any microcontroller variant to be defined. A navigation and communication module is available as an extension module.

As shown in Figure 3, the kit includes a WVGA touch-screen TFT display, and all the connectors and power supplies needed to begin designing immediately.

The preconfigured microcontroller (Figure 4) has a series of integrated interfaces, and provides a graphics accelerator and an audio processor, in addition to an application processor. A demonstration application implements an MP3 player with a graphical user interface and touch-screen operation, and supporting various music sources including SD boards, USB sticks, hard disks/CDs, and MOST units.

SUMMARY

OEM infotainment equipment is coming under increasing pressure from units produced by the entertainment-electronics industry, because the latter’s price/performance ratio appears to be significantly better. Here pure hardware costs play only a minor role, compared with software development, platform maintenance, and testing. One way to improve the unfavorable cost structure is therefore to introduce an open system architecture, as opposed to the proprietary microcontroller architectures currently used, one that is open, scalable, flexible, and secure, and at the same time offers an attractive price/performance ratio. The parameterized infotainment system PARIS, which is an open architecture, can offer a basis for the cost-effective, manufacturer-independent, next-generation infotainment system.





Click here for the illustrations:

Figure 1, Figure 2, Figure 3, Figure 4