Active objects in the UML specification are the roots of threads of control in multitasking systems and engage one another asynchronously via events. The UML further proposes the UML variant of statecharts, with which to model the behavior of eventdriven active objects. This class describes a minimal implementation of the activeobject computing model in form of an application framework&#151a reusable infrastructure for executing active objects tailored for the domain of embedded real-time systems. The paper explains the inner workings of the framework and shows you how to combine it with an RTOS (iC/OS-II). You will learn that active object-based computing avoids most pitfalls of traditional multithreading (such as race conditions or priority inversions), while reaping all the benefits of effective concurrent designs (such as low latencies and good CPU utilization).