RTOS Basics and Application: RTOS Mechanisms and their Application in Runtime Architectures for Embedded and Real-Time Systems - Face-to-Face Training

RTOS Basics and Application: RTOS Mechanisms and their Application in Runtime Architectures for Embedded and Real-Time Systems - Face-to-Face Training

Content

General Introduction: Real-Time Operating Systems

• Key terminology (operating system, real-time, task, multitasking, scheduler)
• Classification of embedded systems
• Classification of operating system types
• Requirements for the operating system, hardware, development tools
• License models
• OSAL Operating System Abstraction Layer
• POSIX (pThread)
• Benefits, advantages and disadvantages when using an operating system
• Practical example: Splitting an application into tasks

Process/Thread/Task Management

• Differentiation between process, task and thread
• Task states and transitions
• Task properties and multiple instantiation
• Specific tasks
• Task context switch and hook routines
• Design aspects for tasks
• Schedulers and their algorithms (endless loop, time-triggerd, priority, time slice, round robin, EDF earliest deadline first)
• Scheduler functionality and design aspects
• Selecting the right scheduler
• Typical use in embedded software applications
• API (application programming interface) examples
• Exercise: Programming a task, instantiating it twice with different priority combinations; subsequent analysis of the behavior

Interrupt Management

• Interrupt processing with and without operating system
• Interrupt latency and interrupt blocking time
• Prioritization
• Interrupt service routines
• Interrupt threads/tasks
• Design notes
• API (application programming interface) examples
• Exercise: Programming an interrupt service routine and a task to service an AD converter

Time Management

• System tick and configuration
• Delay, timeout, interval, software watchdog, alarm timer
• Typical use in embedded software applications
• API (application programming interface) examples
• Exercise: Programming interval timer controlled task execution

Coordination Mechanisms: Synchronization

• Events, signals: global, local, single, as group, with/ without parameters
• Semaphore, promise and future
• Typical use in embedded software applications
• API (application programming interface) examples
• Exercise: Programming synchronization between an interrupt service routine and a task

Coordination Mechanisms: Resource Management

• Race conditions
• Resource: definition, granularity and blocking times
• Semaphore, mutex, critical section, condition variable, spinlock
• Problem scenarios: deadlock and priority inversion
• Solutions: priority inheritance, priority ceiling etc.
• Reader/ writer patterns
• Typical use in embedded software applications
• API (application programming interface) examples
• Exercise: Programming protected access to a resource shared by two tasks

Communication Mechanisms

• Message concepts: system local and cross-system
• Shared memory, mailboxes, queues, message buffer, pipes, message based, socket
• Typical use in embedded software applications
• API (application programming interface) examples
• Exercise: Programming communication between an interrupt service routine and a task and between two tasks using the mailbox concept

Memory Management

• Memory segments (BSS, stack, heap)
• Stack monitoring
• Dynamic memory management
• Memory pools and memory blocks
• Pool allocation pattern: memory pools and memory blocks
• MPU (memory protection unit) and MMP (memory management unit) support
• Typical use in embedded software applications
• API (application programming interface) example
• Identifying risks and avoiding pitfalls

Input/Output Management

• Software layer architecture
• Driver concepts
• Examples with serial and Ethernet communication
• Typical use in embedded software applications
• API (application programming interface) example

Debugging at Operating System Mechanism Level

• Tracing at operating system level
• Introduction and assessment of tracing and visualization alternatives
• Presentation with logic analyzer and professional trace tools (Percepio Tracealyzer and ARM Keil MDK)

Embedded and Real-Time Software Development Procedure

• From the idea to the final runtime architecture
• Runtime architecture patterns and their use for concrete tasks
• Transformation of an existing software architecture without operating system to an architecture with operating system, with optimized utilization of the OS mechanisms
• Introduction and comparison of different runtime architecture concepts - with and without operating system
• Predictability and calculability of various runtime architecture concepts
• Guidelines for selecting the "right" runtime concept
• Practical example: Measurement device application
• Exercise: Development of a suitable runtime architecture for a real embedded system based on drawn up textual requirements and a software architecture

Multicore and Multiprocessor Aspects

• Hardware and software architectures
• Task assignment
• Possible operating system applications
• Virtualization and hypervisor
• Interrupt and driver concepts
• Important design aspects

Documentation and Communication

• Suitable modeling formats for a runtime architecture
• Excerpts from UML (Unified Modeling Language)
• Practical tips
• Exercise: Using UML notations and diagrams for modeling the runtime architecture

Operating System Abstraction Layer OSAL

• Description of benefits, advantages and disadvantages
• Programming
• Practical example with FreeRTOSTM

Operating System Selection Guidelines and Product Overview

• Operating system selection guidelines
• Practical tip: Operating system comparison
• Current product overview for embedded software
• Checklist with important selection criteria

Practical Exercises

• Throughout the programming exercise, you will use operating system mechanisms for developing a measurement device application step by step.
• The exercise is performed using the Arm Keil MDK (microcontroller development kit) with real hardware based on an Arm Cortex® microcontroller.
• For the real-time operating system, you choose between FreeRTOS™ and the CMSIS-RTOS standard as operating system abstraction.
• You develop and document a runtime architecture for an electric motor control application using operating system mechanisms.
• The exercises are performed using Enterprise Architect (Sparx Systems) or paper and pencil.

MicroConsult Plus:

• All participants have the following options to further use their exercises and the solutions developed by MicroConsult from this workshop:
• You e-mail the files to your account, or …
• You get access to file download on request.
• For the measurement device application, you get the program code and a UML model as well as a UML model for the electric motor application.
• You get a tool and software component overview including a current operating system overview.
• You also get a checklist with operating system selection criteria.
• You get helpful notation overviews for UML (Unified Modeling Language) and SysML (Systems Modeling Language) in DIN-A3 format.