Products Download Support Contact Company

Meet reliably the deadlines with

Simple to use and learn - easier to meet your deadlines
Fast and deterministic - easier to meet the system response deadlines

ReaGOS offers safe, effective, and simple solutions to real-time challenges. For example the priority ceiling protocol is used for shared resource locking to avoid priority inversion.

ReaGOS applications: wood milling machine, 
treadmill controller

ReaGOS is a preemptive single-stack kernel. Its main advantages are fast scheduling and small footprint. The kernel is generated automatically from a high level graphical description of the application, so, much of run-time setup and lookup can be avoided.

Operating principles

  • preemptive scheduling with static priorities
  • message based inter -task communication
  • interrupts are handled directly by device specific interrupt handlers
  • all tasks share the same stack
  • event driven
  • scheduling of lower priority tasks can be interrupted for a higher priority task


  • allows fast response times for some urgent events while heavy computation is under execution
  • supports data-flow based concurrent software architecture
  • support multiple waiting: any event concerning the task activates the task as soon as possible
  • support accurate timing without drift; it is easy to implement precisely timed sequences
  • supports easy implementation of inter-task data flows with user definable data types and static buffering
  • is based on static data structures for deterministic behaviour
  • supports fast and small final system code including the application and the kernel
  • supports straightforward and effective interrupt processing
  • includes no excess operating system functions
  • is portable at the source code level
  • is configured and interfaced automatically to application


  • Okkonen Ari, et al., ReaGOS - An Application Specific R/T-OS, 5th Euromicro Workshop on Real-Time Systems, Oulu, Finland, June 22-24, 1993 [PDF]


©2019 OBP Research Oy, c/o Ari Okkonen, Mielikintie 6 A 7, FI-90550 OULU, FINLAND
Tel: +358 40 542 2059, Email: