This product is developed based on the RI600/4, which conforms to the latest version of μITRON 4.0 specification and with additional memory protection function of the μITRON 4.0 protection extension. Almost all service calls in it except Rendezvous are supported.

Successors:RI600PX Real-time OS for RX Family



  • Conformance with the µITRON4.0 Specification
  • Memory Protection
  • ROM-based implementation
  • Kernel building made easy by the configurator
  • Compatibility with the High-performance Embedded Workshop IDE will help you easily install the OS into your applications
  • Supported compiler: C/C++ Compiler Package for RX Family
  • Learn More

Release Information

Latest Ver.: V.1.01 Release 01
Released: Apr 16, 2013
Details of upgrade (See Tool News)
Operating Environment
Agreement Details
User's Manual: RI600/PX V.1.00 User's Manual (Real-time OS for RX Family with MPU) Rev.1.00 (PDF | English, 日本語)

Target Devices


Additional Details


RI600PX Real-time OS for RX Family


The RI600/PX kernel consists of the following modules. Each module is provided by functions (service calls) .

  • Scheduler
    Manages execution sequence of multiple tasks based on their priority levels.
  • Task management
    Manages task status such as RUNNING, READY, WAITING or SUSPENDED.
  • Task-dependent synchronization
    Changes task status from other task, and synchronizes tasks.
  • Interrupt management function
    Makes a return from the interrupt handler.
  • Time management
    Sets system timer used by RI600/PX kernel and starts user-defined alarm handler and cyclic handler.
  • System configuration management
    Reports information such as version number of RI600/PX kernel.
  • Synchronization/communication
    Carries out synchronization and communication between tasks. The following function modules are available:
    • Event flag
      An object to control the execution of a task according to the AND/OR condition represented by bit pattern.
    • Semaphore
      An object for exclusive control of shared devices and variables for two or more tasks.
    • Mail box
      An object to communicate an arbitrary-length message by pointer passing.
    • Data queue
      An object to perform 1-word (32 bits) communication.
  • Extended Synchronization/Communication
    Carries out synchronization and communication between tasks. The following function modules are available:
    • Message buffer
      Makes use of variable-length data communication to synchronize tasks.
    • Mutex
      Makes use of priority ceiling protocol for avoiding priority inversion to synchronize tasks.
  • Memory pool management
    Dynamically allocates/frees memory area used by tasks. Enables efficient use of memory.
  • Task exception handling function
    Controls execution of task exceptions by, for example, defining or activating a task exception.
  • Cyclic handler function
    Controls the execution of a handler activated periodically.
  • Alarm handler function
    Controls the execution of a handler activated at the specified relative-time.
  • Memory protection function
    The following functions are available:
    1. Detection of illegal access by tasks
    2. Protection of stack for task
    3. Detection of illegal access by the kernel

Kernel specifications

Target device RX600 series with MPU (Memory Protection Unit)
Maximum number of tasks 255
Number of priority levels 255
(Time takes for a target task to be executed
after the wup_tas is issued.)
3.2 microseconds
(RX630, 100MHz)
Kernel code size From 6.3K bytes to 33.5K bytes
Kernel RAM usage per task data : 20 bytes
stack : 44 bytes


Provided items Explanation Note
Kernel source program Kernel source program Provided only with mass- production licenses which include source code.
Kernel library Kernel library for system building Compliant with big/little endian
Standard header files ・ITRON specification common definition files
・Kernel specification definition files
・Other definition files
Header files are provided both in C languages
Command line configurator
Outputs all types of definition files from the cfg file that describes the structure parameters in text.
Table generation utility
Generates the Interrupt Vector Table and Service Call Jump Table.
Manual User's manual PDF format

Processing Flow