FreeRTOS is a market leading RTOS from Real Time Engineers Ltd. that is professionally developed, strictly quality controlled, robust, supported, and free to embed in commercial products without any requirement to expose your proprietary source code.
FreeRTOS is very strictly quality managed, not just in software coding standards and look and feel, but also in implementation.
FreeRTOS never performs a non-deterministic operation, such as walking a linked list, from inside a critical section or interrupt.
The efficient software timer implementation does not use any CPU time unless a timer actually needs servicing. Software timers do not contain variables that need to be counted down to zero.
Lists of Blocked (pended) tasks do not require time consuming periodic servicing.
The FreeRTOS queue usage model manages to combine simplicity with flexibility (in a tiny code size) - attributes that are normally mutually exclusive.
FreeRTOS queues are base primitives on-top of which other communication and synchronisation primitives are build. The code re-use obtained dramatically reduced overall code size, which in turn assists testing and helps ensure robustness.
μC/OS-II is a portable, ROMable, scalable, preemptive, real-time deterministic multitasking kernel for microprocessors, microcontrollers and DSPs.
Offering unprecedented ease-of-use, μC/OS-II is delivered with complete 100% ANSI C source code and in-depth documentation.
μC/OS-II manages up to 250 application tasks. μC/OS-II includes: semaphores; event flags; mutual-exclusion semaphores that eliminate unbounded priority inversions; message mailboxes and queues; task, time and timer management; and fixed sized memory block management.
μC/OS-II’s footprint can be scaled (between 5 Kbytes to 24 Kbytes) to only contain the features required for a specific application. The execution time for most services provided by μC/OS-II is both constant and deterministic; execution times do not depend on the number of tasks running in the application.
The Keil RTX is a royalty-free, deterministic Real-Time Operating System designed for ARM and Cortex-M devices. It allows you to create programs that simultaneously perform multiple functions and helps to create applications which are better structured and more easily maintained.
RTX is included in MDK-ARM - No additional cost to use a commercial level RTOS.
RTX is Royalty-Free - No on-going costs.
Market Leading RTOS - Be confident in using RTX in your application.
Flexible Scheduling - Choose the best scheduling for your application.
Deterministic Behavior - Known behavior for time critical tasks.
Designed for Embedded Systems - Uses the minimum amount of system memory.
Easy to Use - Short learning cycle, faster product development.
Source Code - Use it for certification.
Support - Help when you need it.
TI-RTOS offers the following components:
TI-RTOS Kernel (formerly known as SYS/BIOS) provides deterministic preemptive multithreading and synchronization services, memory management, and interrupt handling. TI-RTOS Kernel is highly scalable down to a few KBs of memory.
TI-RTOS SSL provides TLS/SSL and DTLS along with an extensive cipher library.
TI-RTOS Networking (formerly known as the NDK) provides an IPv4 and IPv6-compliant TCP/IP stack along with associated network applications such as DNS, HTTP, and DHCP.
TI-RTOS File System is a FAT-compatible file system based on the open source Fatfs product.
TI-RTOS USB provides both USB Host and Device stacks, as well as MSC, CDC, and HID class drivers.
The TI-RTOS IPC provides efficient interprocessor communication in multicore devices.
TI-RTOS Instrumentation allows developers to include debug instrumentation in their application that enables run-time behavior, including context-switching, to be displayed by system-level analysis tools.
TI-RTOS Drivers and Board Initialization provides a set of device driver APIs, such as UART and IIC, that are standard across all devices, as well as initialization code for all supported boards. All driver and board initialization APIs are built on the MSPWare libraries for the MSP430 and MSP432 devices.
FreeRTOS Technology Highlights
Pre-emptive scheduling option
Easy to use message passing
Co-operative scheduling option
Round robin with time slicing
Mutexes with priority inheritance
6K to 10K ROM footprint
Configurable / scalable
Binary and counting semaphores
Very efficient software timers
Some ports never completely disable interrupts
Easy to use API
The features of µC/OS-II include:
Preemptive multitasking real-time kernel
Delivered with complete, clean, consistent, 100% ANSI C source code with in-depth documentation.
Mutual exclusion semaphores with built-in priority ceiling protocol to prevent priority inversions
Timeouts on ‘pend’ calls to prevent deadlocks
Up to 254 application tasks (1 task per priority level), and unlimited number of kernel objects
Highly scalable (6K to 24K bytes code space, 1K+ bytes data space)
Very Low Interrupt Disable Time
Third party certifiable
Royalty-free, deterministic RTOS with source code
Flexible Scheduling: round-robin, pre-emptive, and collaborative
High-Speed real-time operation with low interrupt latency
Small footprint for resource constrained systems
Unlimited number of tasks each with 254 priority levels
Unlimited number of mailboxes, semaphores, mutex, and timers
Support for multithreading and thread-safe operation
Kernel aware debug support in MDK-ARM
Dialog-based setup using µVision Configuration Wizard