Newbie problems

nobody wrote on Thursday, May 26, 2005:


I have just started to learn about RTOS.

I have managed to got the demo for avr work on my atmega128L with stk500 & stk501.

Now i try to add a task to the demo version for avr but the system seems to hang in my taskcreate routine.

Anybody who has the time to explain or has some code that i can add to the demo for example toggle a led connected to porta or something so i can learn how to create a very simple task to start with.


nobody wrote on Thursday, May 26, 2005:

Take a look at the previous thread -

The Mega128 has more RAM than the 323 - for which the FreeRTOS download is configured.  Try increasing the heap size.  To do this look in the file FreeRTOS/Demo/AVR_ATMega323_WinAVR/FreeRTOSConfig.h (assuming you are using GCC).  In this file you will see the definition configTOTAL_HEAP_SIZE - you can increase this to 2500 (or more).  This will give more RAM to the kernel so it can create more tasks.

To see a simple task that simply flashes an LED at a fixed rate look at the file FreeRTOS/Demo/Common/Minimal/Flash.c.  This creates three identical tasks that do just this.

nobody wrote on Friday, May 27, 2005:

Thanks for the help!!!
It works now when i increased the heap size.