|Written in||C, Assembly language|
|OS family||Real-time operating systems|
|Source model||Open source|
|Latest release||18.2.1 / May 1, 2018|
|Platforms||Intel 80386, ARM7, ARM9, ARM Cortex-M0, ARM Cortex-M3, ARM Cortex-M4, PPC, e200z, Atmel AVR, TI MSP430, STM8, Freescale Coldfire, Renesas H8S|
|License||GPL3 or proprietary|
ChibiOS/RT is designed for embedded applications on 8, 16 and 32 bit microcontrollers; size and execution efficiency are the main project goals. As reference, the kernel size can range from a minimum of 1.2 Kib up to a maximum of 5.5 KiB with all the subsystems activated on a STM32 Cortex-M3 processor. The kernel is capable of over 220,000 created/terminated threads per second and is able to perform a context switch in 1.2 microseconds on an STM32 @ 72 MHz. Similar metrics for all the supported platforms are included in the source distribution as test reports.
The ChibiOS/RT microkernel supports:
- Preemptive multithreading
- 128 priority levels
- Round-robin scheduling for threads at the same priority level
- Software timers
- Counting semaphores
- Mutexes with support for the priority inheritance algorithm
- Condition variables
- Synchronous and asynchronous Messages
- Event flags and handlers
- Synchronous and asynchronous I/O with timeout capability
- Thread-safe memory heap and memory pool allocators.
- Hardware Abstraction Layer with support for ADC, CAN, GPT (general-purpose timer), EXT, I²C, ICU, MAC, MMC/SD, PAL, PWM, RTC, SDC, Serial, SPI, and USB drivers.
- Support for the LwIP and uIP TCP/IP stacks.
- Support for the FatFs file system library.
All system objects, such as threads, semaphores, timers, etc., can be created and deleted at runtime. There is no upper limit except for the available memory. In order to increase system reliability, the kernel architecture is entirely static, a memory allocator is not required (but is available as an option), and there are no data structures with upper size limits like tables or arrays. The system APIs are designed to not have error conditions such as error codes or exceptions.
- ST STM32F1xx, STM32F2xx, STM32F3xx, STM32F4xx, STM32L1xx, STM32F0xx
- ST STM8S208x, STM8S105x, STM8L152x
- ST/Freescale SPC56x / MPC56xx
- NXP LPC11xx, LPC11Uxx, LPC13xx
- NXP LPC2148
- Atmel AT91SAM7S, AT91SAM7X
- Atmel Mega AVR
- TI MSP430x1611
- TI TM4C123G and TM4C1294
- Microchip PIC32MX
It is also possible to run the kernel in a Win32 process in a software I/O emulation mode, allowing easy application development without the need for physical hardware. An example is included for MinGW compiler.
ChibiOS/RT is fully supported by the GUI toolkit µGFX. µGFX was formerly known as ChibiOS/GFX.