On-board System

Here, We explane implementation of the On-borad machine in the Internet car. A On-borad machine(SIC2000) is central hardware of the Internet automobile system, and is the On-borad computer system designed for the pratical durability in the car.

SIC2000 is the exclusive hardware designed for the demand as a On-board computer system of performing an Internet connectivity based on an old experience of the Internet automobile project. SIC2000 consists of a main part and two portions of a controller. In a main part portion, an operating system operates and proccess the practice of applecation and various kinds of sensor information collected from cars. A controller is a user's only interface, and it is designed so that it can be stored in the dashboard of a car. A controller is equipped with a power supply, Light Emitting Diode which displays a character, other switches, and a serial interface. A main part and a controller are connected by the serial cable.

Feature

At first, It is the point that memory storage is constituted based on ROM. On-borad hardware must assume the use under cruel environment, such as vibration and change of temperature. If vibration generated by run of a car is taken into consideration, it is not desirable to use weak equipment for vibration with a rotated type like a hard disk. Therefore, in SIC2000, EPROM and Flash ROM are used as a non-volatilized memory storage.

Second, it is the point of equipping with abundant I/O interfaces. In order to collect information from various sensors , many I/O interfaces are needed in Internet Cars. Five serial interfaces, four PCMCIA (Type2) slots, and one connector for collection of various sensor information are prepared in SIC2000 main part.

Third, it is the point that the device is not seen such as the display, a keyboard, and a mouse looked at by the usual computers such as PC or WorkStation. These devices is not equipped because of useing on board. Fundamentally, a user performs operation and the check of a state only in a controller part.

Fourth, the feature of a power supply portion can be pointed. In consideration of fully use on board, it is designed which can respond also to cutting the power supply which is not expected. The backup mechanism is incorporated.

On-board operating system

BSD is used for the operating system of a On-board machine in the Internet automobile project. The main reason is because it is mostly used as that it is the operating system in which BSD had a high actual result in employment by the Internet, and a test bed of an advanced network protocol. The IPv6 protocol stack by KAME can be used in BSD, including Mobile IP. In BSD we chose NetBSD which has also the feature of supporting many architecture.

Starting program

The memory storage of a SIC2000 main-part part has two, EPROM (512kB) and FlashROM (8MB), as a thing of non-volatility. And there are DIMM (64MB) and PBSRAM (1MB) as a thing of volatility. It is necessary to store an operating system and application in a nonvolatile memory, but because if the problem of size. application must be inevitably stored in the memory storage of the exteriors, such as Flash ROM or an ATA card, As a precondition of hardware, there is a thing that the program in EPROM is performed after a power supply injection. Therefore, the starting program is stored in EPROM. And it is possible to store not only the starting system but also operating system in EPROM, but to store operating system in Flash ROM is more suitable becase of the cost which is needed for upgrating or maintenance.

Development environment

We chooose a FreeBSD at a Development environment and uses the cross compiler on it. As a SIC2000 main-part is built from MIPS architecture, a cross compiler is needed on the development on PC architecture. the target if a cross compiler is able to be made to the object file which operates by SIC2000 also on FreeBSD as the MIPSVR4300 architecture. The software used for construction of development environment is as follows.

The development manual for SIC2000 (Japanese)