Pharos is a free open-source RTOS for secure, safe and real-time systems with the following characteristics:
- Memory and enhanced time partitioning (TSP)
- Native support for sporadic, periodic and aperiodic threads
- Fixed-priority preemptive scheduler
- Execution time protection (threads are prevented from executing for more time than they are configured to)
- Small size (full image has ~100 to 300KiB text, ~30KiB data)
- Hard real-time determinism
- Fast critical sections
- Prioritized nested interrupts
- inter-partition communication with filters to protect unwanted access
- Multicore support (RMP)
- Supports ARM9, Cortex-A/R/M and Aarch64, RISC-V64 (64 bits)
- The complete TestSuite (see below information) is run successfully for each platform in each release
- Tested: more than 170 KLOC of requirement-based tests, executed for each board at each release
- Up-to-date User Manual also available
See our wiki page for more information.
Features
- RTOS
- TSP
- Mixed criticality
- Memory protection
- Time protection
- Fixed-priority preemptive scheduler
- Hierarchical scheduler (e.g. ARINC 653) - optional
- Static configuration (default & recommended)
- Periodic threads
- Sporadic threads
- Aperiodic threads
- Nested prioritized interrupts
- Fast critical sections
- Flexible Inter-partition filters
- Multicore support (RMP)
- Fast & scalable inter-core communication
- Customizable CPU support
- Zero-copy transfer for large data between partitions (Channels)
- Zero-copy transfer for large data within partition (lw queue)
- Ceiling/counting/mutex semaphores
- Software timers
- Dynamic memory allocation - optional
- "Small" size
- 32 bit RTOS
- 64 bit RTOS
- ARM9
- Cortex-A
- Cortex-R
- Cortex-M
- Aarch64
- RISC-V (64 bits)
License
Apache License V2.0
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User Reviews
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Have been trying Pharos for a month and it seems like a cool RTOS. The memory and time protection work OK. Had to spend some time configuring it though (cross-compiler) and could use some more features like dynamically creating objects. Keep up the good work ;)