DAY 1
Cortex-M resources used by RTOS
- Cortex-M Architecture Overview
- Two stacks pointers
- Different Running-modes and Privileged Levels
- MPU Overview
- Systick Timer Description
- Exception / Interrupt Mechanism Overview
- Interrut entry and return Overview
- SVC / PendSV / Systick Interrupt Presentation
- Developing with the IDE
Lab: Interrupt Management on Cortex-M4
Element of a Real-Time system
- Base Real-Time concepts
- The Real-Time constraints
- Multi-Task and Real-Time
- Tasks and Task Descriptors
- Content of the task descriptor
- List of task descriptors
- Context Switch
- Task Scheduling and Preemption
- Tick based or tickless scheduling
- Scheduling systems and schedulability proof
- Fixed priorities scheduling
- RMA and EDF scheduling
- Scheduling through FreeRTOS
- Deterministic preemptive scheduling
- Scheduling strategies
- Cooperative scheduling
- Hybrid scheduling
Lab: Analyse a Context Switch
DAY 2
Task Management
- The Task life-cycle
- Creating tasks
- Deleting tasks
- The Endless-loop pattern
- Task Priorities
- Assigning task priorities
- Changing task priorities
- The idle task
- Timing
Lab: Managing tasks
Resource Management
- Mutual exclusion through FreeRTOS
- Critical sections (interrupt masking)
- Suspending (locking) the scheduler
- Mutexes
- Mutexes concepts
- Mutex or Semaphore
- Recursive or not recursive mutexes
- Priority inversion problem
- Priority inheritance (the automatic answer)
- Priority ceiling (the design centric answer)
- Gatekeeper tasks
Lab: Implement mutual exclusion between tasks
Synchronization Primitives
- Introduction
- Waiting and waking up tasks
- Semaphores
- Events
- Mailboxes
- Binary Semaphores through FreeRTOS
- Give a Binary Semaphore
- Take a binary Semaphore
- Queue Management through FreeRTOS
- Creation
- Sending on a queue
- Receiving from a queue
- Data management
- Sending compound types
- Transferring large data
- Event groups
Lab: Synchronizing a task with another one through binary semaphores
Lab: Synchronizing a task with another one through queues
DAY 3
Parallelism Problems Solution
- Parallel programming problems
- Uncontrolled parallel access
- Deadlocks
- Livelocks
- Starvation
Lab: The producer-consumer problem, illustrating (and avoiding) concurrent access problems
Lab: The philosopher’s dinner problem, illustrating (and avoiding) deadlock, livelock and starvation
Interrupt Management
- Need for interrupts in a Real-Time system
- Software Interrupt
- Time Interrupts
- Device Interrupts
- Level or Edge interrupts
- Hardware and Software acknowledge
- Interrupt vectoring
- Interrupts and scheduling
- Deferred interrupt processing through FreeRTOS
- Tasks with interrupt synchronization
- Using semaphores within an ISR
- Counting semaphores
- Using queues within an ISR
- FreeRTOS interrupt processing
- Writing ISRs in C
- Interrupt safe functions
- Interrupt nesting
Lab: Synchronize Interrupts with tasks
Software Timer
- The Timer Daemon Task
- Timer Configuration
- One-shot / Auto-reload Timer
- Software Timer API
- Deferred interrupt handling
Lab: Implement Soft Timers
FreeRTOS-MPU
- The Cortex/M MPU
- User and privileged modes
- Access permissions
- Defining MPU regions
- Overlapping regions
- Predefined regions
- Programmer-defined regions
- Needed linker configuration
- Practical usage tips
Lab: Implement protected memory regions
OPTIONAL ADDITIONAL TOPICS
Data structures
- Need for specific data structures
- Data structures
- Linked lists
- Circular lists
- FIFOs
- Stacks
- Data structures integrity proofs
- Assertions
- Pre and post-conditions
- Thread safety
Lab: Build a general purpose linked list
Memory Management
- Memory management algorithms
- Buddy System
- Best fit / First Fit
- Pools Management
- FreeRTOS-provided memory allocation schemes
- Allocate-only scheme
- Best-fit without coalescing
- Thread-safe default malloc
- Checking remaining free memory
- Adding an application-specific memory allocator
- Memory management errors
- Stack monitoring
Lab: Write a simple, thread safe, buddy system memory manager
Lab: Write a generic, multi-level, memory manager
Lab: Enhance the memory manager for memory error detection
Trouble Shooting
- Checking for stack problems
- Common pitfalls
