| CMSIS-RTOS RTX Version 4.75 CMSIS-RTOS RTX: Real-Time Operating System for Cortex-M processor-based devices

- RTX

- Main Page
- Usage and Description
- Reference

Technical Data

This section lists the technical data of CMSIS-RTOS RTX.

Description | Limitations
--- | ---
Defined Tasks | Unlimited
Active Threads | 250 max
Mailboxes | Unlimited
Semaphores | Unlimited
Mutexes | Unlimited
Signals | 16 per thread
Timer Callbacks | Unlimited
Code Space | < 5.0 Kbytes
RAM Space for Kernel | 300 bytes + 128 bytes Main Stack
RAM Space for a Thread | StackSize + 52 bytes
RAM Space for a Mailbox | MaxMessages * 4 + 16 bytes
RAM Space for a Semaphore | 8 bytes
RAM Space for a Mutex | 12 bytes
RAM Space for a User Timer | 20 bytes
Hardware Requirements | SysTick timer or other hardware timer
Thread context switch time | < 2.6 usec @ 72 MHz
Interrupt lockout time | Not disabled

Note
  Unlimited means that the RTX kernel does not impose any limitations on the number. However, the available system memory resources limit the number of items you can create.
  RAM requirements depend on the number of concurrently running threads.
  The code and RAM size is calculated for ARMCC Compiler when using the MicroLib runtime library.

# osWait

The generic wait function osWait is currently not supported by CMSIS-RTOS RTX.