Posted on March 28, 2016 at 17:57Hi all,
I have a serious issue with the EWI (Early wakeup interrupt) of the WWDG.
I'm using STM32F103 and I'm based on the example of the firmware libraries, I add the configuration of the EWI interrupt : the source code :
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/* WWDG configuration */
/* Enable WWDG clock */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_WWDG, ENABLE);
/* On Value line devices, WWDG clock counter = (PCLK1 (24MHz)/4096)/8 = 732 Hz (~1366 us) */
/* On other devices, WWDG clock counter = (PCLK1(36MHz)/4096)/8 = 1099 Hz (~910 us) */
WWDG_SetPrescaler(WWDG_Prescaler_8);
/* Set Window value to 80; WWDG counter should be refreshed only when the counter
is below 80 (and greater than 64) otherwise a reset will be generated */
WWDG_SetWindowValue(80);
/* - On Value line devices,
Enable WWDG and set counter value to 127, WWDG timeout = ~1366 us * 64 = 87.42 ms
In this case the refresh window is: ~1366us * (127-80) = 64.20 ms < refresh window < ~1366us * 64 = 87.42ms
- On other devices
Enable WWDG and set counter value to 127, WWDG timeout = ~910 us * 64 = 58.25 ms
In this case the refresh window is: ~910 us * (127-80) = 42.77 ms < refresh window < ~910 us * 64 = 58.25ms
*/
WWDG_EnableIT();
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
NVIC_InitStructure.NVIC_IRQChannel = WWDG_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
WWDG_ClearFlag();
WWDG_Enable(127);
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The interrupt service routine code is :
void WWDG_IRQHandler(void)
{
if (WWDG_GetFlagStatus() != RESET)
{
WWDG_SetCounter(127);
WWDG_ClearFlag();
}
}
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The Problem is that the STM32F103 goes directly to EWI interrupt as soon as WWDG is enabled.
Can anyone help me please; it is urgent?
Thanks,
john
#stm32f103--wwdg---ewi
