Remarks: This Software Architecture Specification is part of the SafeQP Certification Kit↑, but applies to the whole QP Framework family↑. This document is the best source of information about the master plan for the overall organization of QP Framework as well as QP Applications derived from the framework. The detailed QP Framework design is described in a separate document: QP Software Design Specification [DOC_SDS_QP].

Revision History

QP version	Document revision	Date (YYYY-MM-DD)	By	Description
7.3.4	A	2024-05-05	MMS	Initial release for IEC-61508 SIL-3 and IEC-62304 Class-C.
7.4.0	B	2024-07-30	MMS	Updated for QP 7.4.0.
8.0.0	C	2024-11-17	MMS	Updated for QP 8.0.0.

Purpose and Scope

This Software Architecture Specification (SAS) with Unique Identifier: DOC_SAS_QP describes the software architecture of QP Framework that satisfies the QP Software Requirements Specification (DOC_SRS_QP) and the QP Software Safety Requirements Specification (DOC_SSR_QP).

Note: The architecture specified in this document can be ultimately implemented in various programming languages, so this document applies to a whole family of QP Real-Time Embedded Frameworks (RTEFs), currently consisting of QP/C, SafeQP/C, QP/C++, and SafeQP/C++ frameworks implemented in C and C++, respectively. Other possible implementations (e.g., QP/Rust) of these requirements and features might be added in the future.

Architectural Viewpoints

The QP Framework architecture is presented according to the international standard [ISO-42010:2022] Architecture Description by means of the following architectural viewpoints, each consisting of various architectural views:

Stakeholders

This Software Architecture Specification is primarily intended for the following stakeholders:

Application Developers who develop QP Applications based on the QP Framework,
Software Architects,
Quality-Assurance Engineers,
System Engineers,
Test Engineers, as well as
Managers who oversee the software development.

Concerns

This architecture specification addresses the following general concerns (understood here as topics of interest [ISO-42010:2022]):

the applied programming paradigms and software technologies;
the context, layering, and assignment of functionality to QP Framework and QP Application;
the interface between QP Framework and the QP Application based on the framework as well as between QP Framework and the Operating System underlying the framework;
main policies with respect to resource management and ownership.

Document Conventions

Architecture Specification UIDs

For traceability, this Software Architecture Specification uses the Unique Identifiers (UIDs) with the following structure:

 +---------------- [1] Work artifact class (e.g., 'SAS' for Software Architecture Specification)
 |  +------------- [2] Project identifier ('QP' for QP Framework or 'QA' for QP Application)
 |  |   +--------- [3] Architecture view (e.g., 'OSAL' for OS Abstraction Layer)
 |  |   |
SAS_QP_view

Examples: SAS_QP_OSAL, SAS_QP_OO

UML Semantics

Most diagrams presented in this Software Architecture Specification conform to the the established and precisely defined semantics of the Unified Modeling Language [UML2.5:17]. In case a diagram uses any non-normative" elements, the semantics of those are explained in the diagram description.

References

[ISO-42010:2022]	ISO/IEC/IEEE, "International Standard ISO/IEC/IEEE 4210, Software, systems and enterprise engineering - Architecture description", 2022
[DOC_SRS_QP]	Software Requirements Specification
[DOC_SSR_QP]	Software Safety Requirements
[DOC_SDS_QP]	Software Design Specification
[QM-Tool:2024]	Quantum Leaps, QM Model-Based Design Tool↑
[OO-in-C:2023]	Object-Oriented Programming in C↑, Quantum Leaps, GitHub, 2023
[UML2.5:17]	"OMG Unified Modeling Language (OMG UML) Version 2.5.1", document formal/2017-12-05, OMG 2017

Technology Viewpoint