Keil Logo Arm Logo

Technical Data

Description ARM7™/ARM9™ Cortex™-M
Defined Tasks Unlimited Unlimited
Active Tasks 250 max 250 max
Mailboxes Unlimited Unlimited
Semaphores Unlimited Unlimited
Mutexes Unlimited Unlimited
Signals / Events 16 per task 16 per task
User Timers Unlimited Unlimited
Code Space <4.2 Kbytes <4.0 Kbytes
RAM Space for Kernel 300 bytes +
80 bytes User Stack
300 bytes +
128 bytes Main Stack
RAM Space for a Task TaskStackSize + 52 bytes TaskStackSize + 52 bytes
RAM Space for a Mailbox MaxMessages * 4 + 16 bytes MaxMessages * 4 + 16 bytes
RAM Space for a Semaphore 8 bytes 8 bytes
RAM Space for a Mutex 12 bytes 12 bytes
RAM Space for a User Timer 8 bytes 8 bytes
Hardware Requirements One on-chip timer SysTick timer
User task priorities 1 - 254 1 - 254
Task switch time <5.3 µsec @ 60 MHz <2.6 µsec @ 72 MHz
Interrupt lockout time <2.7 µsec @ 60 MHz Not disabled by RTX

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.
  • The default configuration of the RTX kernel allows 10 tasks and 10 user timers. It also disables stack checking by default.
  • In the RTX kernel, Event is simply another name for signal.
  • RAM requirements depend on the number of concurrently running tasks.
  • The code and RAM size was calculated for MicroLib runtime library.

Keil logo

Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.