IWDG and NVIC_SystemReset on Keil MCBSTM32

Systemreset:
Setting bit SYSRESETREQ to request an systemreset will only work at privileged mode. If you try to set this bit at unprivileged mode a hardfault ecxeption occurs.

Watchdog:
It is possible that the watchdog timer keeps running during debug stop. Please have a look to the STM32DBG.ini file and check the behaviour during debug stop.

Hi Raphael,

thnx for the reply but... I'm not sure I did undertsand correctly:

1) Systemreset
I do NOT change any privilege at startup, so the micro should start in thread/privileged mode, shouldn't it ?
As a result, setting the SYSRESETREQ should cause a reset. Anyway, the debugger shows that the execution halts in the while(1); loop after bit set, and never enters the default HardFault_Handler.
??

2) Watchdog
I checked the STM32DBG.ini file and confirm that IWDG does NOT stop when core is haltded (i didn't stop anyway, debugger was just running).
I also tried to switch to SW insted of JTAG and assigned an alternate GPIO function to jtag reset signal, but the behavior is the same.

Any other hint ??

Hi Marco

Systemreset:
I use the following code to request a systemrest out of unprivileged mode.

void __svc(1) PeriResetSystemSVC( void );
void __SVC_1                    ( void ) {

    // note: beginning of protected function to reset the system
    __disable_irq();

    // set software reset flag
    NVIC_GenerateSystemReset();
    // hack: for debug endless loop should never be reached
    while( 1 ) {
        __nop();
    }
}

The differences are that the irq get disbaled and that I use an older version of the ST fimrware lib. But it isn't obviously to me, way your code isn't running.

Watchdog:
Perhaps you have to disable the "run to main()" check box at the debug settings?

Dear sir:
Like the topic.
Where i can get it.
Thank you very much.

Hi Raphael,

1 SystemReset
My code is much like your:

if (ProtectedPages != 0x00000000) {

  //bootloader pages are not protected, protect them
  FLASHStatus = FLASH_EnableWriteProtection(D_FLASH_BOOTLOADER_PROTECTED_PAGES);

  Led_1_Turn_On(0,0);  //TODO TEST, remove when done

  // Generate System Reset to load the new option byte values
  __disable_irq();
  NVIC_SystemReset();

} else {

  Led_1_Turn_Off();  //TODO TEST, remove when done

}

But it doesn't work...

2) Watchdog
I disabled the "run to main()" checkbox but nothing changed.

Can I ask you which board are you using (if you're using one...)

No; the topic of this thread is IWDG and NVIC_SystemReset on Keil MCBSTM32

Do not hijack existing threads with unrelated requests!

Also note that it has nothing to do with Keil tools or products - so this isn't even the correct forum in which to ask.

Have you tried google?

Hi Marco

We use our own board. We use the SWD configuration and uLink2 for debugging and programming. The NRST pin is also connected to the SWD connector but the pin B4/TRST isn't connected as ST did at their eval board STM3210B.