I want to add a task in rtos to display an integer for example a counter, i have written the code for this task and i want to know how can i add it to the rtos. thanks.

This is a bit of a vague question.  The best starting point is to take the demo project for your hardware and modify that.  Look in the main.c file – here you will see calls to sTaskCreate().  This takes a pointer to the function you have written to add the function to those already being scheduled. Some of the demo projects already use all the memory available on the hardware so to add a new task you may have to remove one of the existing tasks. Hope this is helpful.

is there a more spesific opinion, what changes shound i do in order to add my code (i think i have enough RAM to do that) thanks

Say your function is like this: void vMyTask( void *pvParameters ) {     for(;;)     {         // Do something     } } Then you need to add a line such as: sTaskCreate( vMyTask, "XYZ", 100, NULL, 2, NULL ); where 100 is the stack size (depends on your function and the port you are using) and 2 is the priority. Please read the API documentation and look at the demo applications where there are many examples.  A good way to learn the system is to step through the code of the existing applications. Regards.