Preface🔗

The acronym scmRTOS stands for Single-Chip Microcontroller Real-Time Operating System.

As indicated by the name, scmRTOS is targeted at single-chip microcontrollers (MCUs), although it can also be used with processors such as Blackfin or Cortex-A.

Purpose🔗

One of the primary objectives in developing this RTOS was to provide the simplest, most minimal, fastest, and most resource-efficient implementation of preemptive multitasking for single-chip MCUs with limited resources that generally cannot be expanded. Although advancements in technology since the introduction of scmRTOS have reduced the emphasis on RTOS efficiency, simplicity, speed, and compact size continue to be advantageous in many applications.

A second key motivation for scmRTOS is its implementation in the C++ programming language. While contemporary C++ has increased in complexity, scmRTOS employs only the fundamental concepts and constructs from the C++98 standard: classes, templates, inheritance, and function name overloading.

In embedded systems development, C++ is sometimes viewed unfavorably due to misconceptions regarding overhead and controllability. In practice, appropriate use of C++ can simplify software development and maintenance, although inappropriate application may produce the opposite result.

scmRTOS prioritizes ease of use. This is facilitated by object-based design, where classes encapsulate internal details and expose only a well-defined interface, thereby minimizing the risk of incorrect usage of operating system components.