Hello, I’d like to know if you can help me.  I port the new free rtos version in a new Cortex-M3 project in IAR.  There is no call in my created task and it is stalled in vPortStartFirstTask() vPortStartFirstTask     /* Use the NVIC offset register to locate the stack. */     ldr r0, =0xE000ED08     ldr r0, [r0]     ldr r0, [r0]     /* Set the msp back to the start of the stack. */     msr msp, r0     /* Call SVC to start the first task. */     svc 0   <<<<<<<<<<<<<<<<<<< STOP HERE What does it mean?  Thanks

Check the vector table, do you have vPortSVCHandler installed as the SVC handler? Look at the file startup_ewarm.c in DemoCORTEX_LM3Sxxxx_IAR_Keil for an example.

Yes I have this handler in the vector.  I wonder if global interrupts are disabled! Regards

Interrupts should be disabled at that point, the svc instruction is synchronous and will execute even when interrupts are disabled.

I got the same problem with 5.30 of Free RTOS. The vector table looks like this: __attribute__ ((section(".isr_vector"))) void (* const g_pfnVectors[])(void) = {     (void (*)(void))((unsigned long)pulStack + sizeof(pulStack)),                                             // The initial stack pointer     ResetISR,                               // The reset handler     NmiSR,                                  // The NMI handler     FaultISR,                               // The hard fault handler     IntDefaultHandler,                      // The MPU fault handler     IntDefaultHandler,                      // The bus fault handler     IntDefaultHandler,                      // The usage fault handler     0,                                      // Reserved     0,                                      // Reserved     0,                                      // Reserved     0,                                      // Reserved     vPortSVCHandler,                        // SVCall handler     IntDefaultHandler,                      // Debug monitor handler     0,                                      // Reserved     xPortPendSVHandler,                     // The PendSV handler     xPortSysTickHandler,                    // The SysTick handler     IntDefaultHandler,                      // GPIO Port A … It should work, but cpu stucks at svc command in vPortStartFirstTask. Can anyone help?

OK, i found the Problem with SVC Command in the Cortex-M3. It is a general problem while debugging with GDB and openocd. During Step-wise debugging, interrupts are disabled. SVC command causes an interrupt, so the command doesn’t work during stepping. I found several suggestion in openOCD forums that i should enable interrupts again with "monitor cortex_m3 maskisr off" in the gdb console. This didn’t work. After 2 days of searching a solution, it has shown that the problem was a wrong openOCD and GDB configuration. (It seems that 99% all problems are openOCD config problems) Now i use openocd from the YAGARTO Homepage ( r1888+patch) with the following openocd Configuration files: interface/luminary.cfg target/lm3s6965.cfg, and following Startup code for GDB: target extended-remote localhost:3333 monitor soft_reset_halt load break main continue Every works now. After startup troubles, the Luminary Cortex-M3 µCs + Codesourcery Lite + FreeRTOS + openOCD + Eclipse works great.