Quantum Leaps

Gene, glad to hear it’s starting to click. In my draft statechart I omitted many details. For example, TRANSACTION_TIMEOUT is generated by a dedicated QTimeEvt instance, separate from the periodic QTimeEvt that produces CONTROL_TICKs. You arm this one‑shot time event immediately after sending the request, and you disarm it when the corresponding TRANSACTION_DONE arrives. The same time event can be reused in both request‑sending states, because the state machine is always in exactly one of them. Hope...

Hi Gene, I suspected from your first draft statechart that not all relevant events were shown. Now that you mention TRANSACTION_DONE, it confirms that your “Sample” is a state that waits for that event. This is the classic request–reply pattern that trips people up. We tend to think of request–response as a single atomic transaction, but architecturally it always consists of three distinct elements: Sending the request — not an event; typically just a function call. Receiving the reply — this is...

Hi Gene, The state machine you posted earlier shows a very common confusion between a statechart and a flowchart. This distinction is explained clearly in the PSiCC2* book (section 2.2.3 State Diagrams versus Flowcharts, p. 61). The key point is that states in a state machine are not stages of processing. A state exists to wait for events and to preserve context between those events. For example, your machine might be in the Ascended state while it is waiting for certain events. When the event NEW_PRESS...

Hi Gene, A non-trivial example of applying QP is the "Fly 'n' Shoot" game used in Chapter 1 of the PSiCC2 book. This example is also explained in the video "Active Objects, Hierarchical State Machines, and Modeling in Practice". In that video I also lay out several architectural guidelines. But, generally, your objectives are: Avoid direct sharing of resources (e.g., I/O devices). Instead of sharing resources directly, encapsulate them inside dedicated AOs. The AOs that manage the resources become...

Hi Gene, A non trivial examle of applying QP is the "Fly 'n' Shoot" game used in Chapter 1 of the PSiCC2 book. This example is also explained in the video " Active Objects, Hierarchical State Machines and Modeling in Practice". In that video, I also provide several architectural guidelines. But, generally: your objective are: Avoid direct sharing of resources (e.g., I/O devices) Instead of sharing resources directly, encapsulate them inside dedicated AOs AOs that manage the resources become the servers...

Hi Tvishy, I understand that your laptop cannot run Windows 11. In that situation, your alternative is to use VSCode on Linux together with the necessary extensions to cross‑compile for the embedded targets used in the course (TivaC LaunchPad or NUCLEO‑C031C6). Unfortunately, getting all of this working on Linux is not trivial. You would need to install and configure VSCode, the C/C++ extensions, the ARM toolchain, and likely OpenOCD or another debug server. This setup requires solid Linux skills...

Hi Julio, Yes — the standard QP/C and QP/C++ editions include support for both FreeRTOS and ThreadX. The SafeQP editions do not yet include ports to third‑party RTOS kernels. Regarding the standard QP frameworks: over the years they have been used extensively in medical devices developed under IEC 62304, including many Class C systems. However, Quantum Leaps was not directly involved in those certification efforts, so we did not own — and therefore could not provide — the certification artifacts...

Hi Julio, Yes — the standard QP/C and QP/C++ editions include support for both FreeRTOS and ThreadX. The SafeQP editions do not yet include ports to third‑party RTOS kernels. Regarding the standard QP frameworks: over the years they have been used extensively in medical devices developed under IEC 62304, including many Class C systems. However, Quantum Leaps was not directly involved in those certification efforts, so we did not own — and therefore could not provide — the certification artifacts...