Hello, i have created a freeRtos project for s32k142 (cortex m4), but when I call vTaskStartScheduler function the application will stop at address 0x0, when i debugged it it seems that this happen exactly at the function "prvPortStartFirstTask " especially here:
__asm volatile(
" ldr r0, =0xE000ED08 \n" /* Use the NVIC offset register to locate the stack. */
" ldr r0, [r0] \n"
" ldr r0, [r0] \n"
" msr msp, r0 \n" /* Set the msp back to the start of the stack. */
" mov r0, #0 \n" /* Clear the bit that indicates the FPU is in use, see comment above. */
" msr control, r0 \n"
" cpsie i \n" /* Globally enable interrupts. */
" cpsie f \n"
" dsb \n"
" isb \n"
" svc 0 \n" /* System call to start first task. */
" nop \n"
);
Hello, thank you for your reply
I have checked the link that you have sent:
Can you put a breakpoint near the beginning of your task(s)
Yes, but it didn’t reach any task
Be sure configASSERT() is defined,
Yes it is
be sure you have a vApplicationMallocFailedHook() installed to catch out-of-memory and/or heap configuration errors.
we are not using it because we have static tasks
Check the priority of the SVC exception.
Yes, and it is 0x00
Does your FreeRTOSConfig.h have these lines: #define vPortSVCHandler SVC_Handler #define xPortPendSVHandler PendSV_Handler #define xPortSysTickHandler SysTick_Handler
Yes i have added them
If all of that fails, can you step through the code and isolate the statement that is causing the hard fault? Note that you will need to put a breakpoint at the beginning of the vPortSVCHandler() to step into that function.
I have put the breakpoint inside the asm code for both functions “prvPortStartFirstTask” and “vPortSVCHandler” but it doesn’t stop on any of them
You may have already checked, but the other possible solution on that thread is to check SCB->VTOR? Is it pointing at your application’s vector table?
I missed this in my reply above. Does program control never reach prvPortStartFirstTask()? I understood from your first post that the issue occurs somewhere inside prvPortStartFirstTask().
Can you post your entire project? Maybe attach it here or upload to github?
yes it reaches “prvPortStartFirstTask” but once i arrive to it if do step over or step into it will go to unknown address, you can see the capture below:
Thank you for your response, I will check them point by point.
I just wanted to add this screen which shows all the informations on SCB register, when it get stuck
“I missed this in my reply above. Does program control never reach prvPortStartFirstTask() ? I understood from your first post that the issue occurs somewhere inside prvPortStartFirstTask() .”
The address of the VTOR register is 0xe000ed08, but the value is 0 as shown in either hex or binary column. After taking svc 0, mcu is jumping to the address stored in VTOR register which is 0.
It does seem like VTOR is not properly. Because, as per the picture above, value at address 0x0 is 0xffffffff. Can you please check the address where the exception vectors are located either from the.map or the linker script and load that value into VTOR by following prvPortStartFirstTask() fails at SVC 0 - Kernel - FreeRTOS Community Forums ?
Hello, but it will be zero only if i try to run it again, in that picture it’s just i have clicked run, that’s why it is set to zero, and i have just figured out that the micro-controller is actually reset, that’s why it went to zero, and when i checked the register that tells the reset reason “RCM” it says that it is a “core lockup reset”.
But if you checked the other picture it will shows the address when i just stuck:
Hi @Zak this problem looks different to me than in the other posts. Your flash-borne vector table appears to be empty. Your picture of the flash contents at 0x00000000 indicates that part of flash (the vector table) is empty. But other pictures indicate that other parts of flash are not empty – they contain code. Pretty odd for your flash image to have code but an empty vector table.
Are you booting from RAM? That might explain how VTOR is 0x1FFFC080.
Can you check what values are in R0 before and after 0x0001242c executes?
Can you post your project on github or attach it here?
Hello guys, thank you all for your help
It worked now, and as always the problem was SCB->VTOR, in my case it was getting 0x1fffc080, which is not correct, the correct address is the beginning of m_data section (0x1fffc0a0), but somehow he is subtracting 0x20 from that whioch leads to VTOR address pointing to another section, i think it’s an alignment problem, because when i started m_data section form the address 0x1fffc100 it worked and the SCB->VTOR address is also 0x1fffc100.
But actually still i have another problem:
Now all the tasks are working but after some time some of them will stop working without any cause, but i will create a new topic for this.
