RX4000

    RX4000 has the following features:
` Conformity with ITRON 3.0 specification
    RX4000 is designed to conform with the ITRON 3.0 specification that defines a typical built-in control OS
    architecture. It implements all ITRON 3.0 functions of up to level S, as well as the level E functions,
    excluding the extended synchronous communication function.
    The ITRON 3.0 specification applies to a built-in, real-time control OS.
` High generality
    In addition to the system calls specified by the ITRON 3.0 specification, RX4000 provides original system
    calls specific to RX4000, so that it can run on more generalized application systems.
    RX4000 can be used to create a real-time, multitasking OS that is compact and optimum for the user's
    needs because the functions (system calls) to be used by the application system can be selected during
    creating the system.
` Realization of real-time processing and multitasking
    RX4000 supports the following functions to realize complete real-time processing and multitasking:
    - Task management function
    - Signal handler function
    - Task-associated synchronization function
    - Synchronous communication management function
    - Interrupt handling management function
    - Memory pool management function
    - Time management function
    - System management function
    - Scheduling function
` Compact design
    RX4000 is a real-time, multitasking OS that has been designed on the assumption that it will be
    incorporated into the target system; it has been made as compact as possible to enable it to be loaded into
    a system's ROM.
` Application utility support
    RX4000 supports the following utility tool to aid in application system construction:
    - System configurator CF4000
` C compiler packages
    RX4000 corresponds to the following VR SeriesTM C compiler packages:
    - CodeWarriorTM (Metrowerks Co., Ltd.)
    -CCMIPE Compiler (Green Hills SoftwareTM Inc.)
` Compatibility with RX830 (ITRON Ver. 3.0) and RX850 Pro
    RX4000 is compatible with RX830 (ITRON Ver. 3.0) and RX850 Pro.

Rapid advances in semiconductor technologies have led to the explosive spread of microprocessors such that they are now to be found in more fields than many would have imagined only a few years ago. In line with this spread, the number of processing programs that must be created for microprocessors is also increasing. This rule of growth makes it difficult to create processing programs specific to given hardware.

For this reason, there is a need for operating systems (OSs) that can fully exploit the capabilities of the latest generation of ever-newer high-performance, multi-function microprocessors.

Operating systems of RX4000 are broadly classified into two types: program-development OSs and control OSs. Programdevelopment OSs are to be found in those environments in which standard OSs (e.g., MOS-DOSTM, WindowsTM, and UNIXTM OS) predominate because the hardware configuration to be used for development can be limited to some extent (e.g., personal computers).

Conversely, control OSs are incorporated into control units. That is, these OSs are found in those environments where standard OSs cannot easily be applied because the hardware configuration varies from system to system and because efficient operation matching the application is required.

To satisfy these market demands, NEC has developed and released not only more powerful microprocessors - VR4100 Series and VR4300 Series - but also the RX4000 operating system, which allows users to exploit the functions of these high-performance microprocessors and supports the systematic creation of software.

RX4000 is a control OS for real-time, multitasking processing; it has been developed to increase the application range of high-performance, multi-function microprocessors and further improve their generality.