Posted on May 23, 2013 at 18:16Hello, everybody
now I use stm32f103r8, I haved followed the reference manual and configured my mcu in to stop mode. And it has been in stopmode, but when i press button to wakeup the mcu, the mcu reset. I print value of register RCC_CSR, it's the default value 0x0c000000.
as descriped above, my problem is why mcu reset when I pressed button to wakeup the mcu?
by the way, I post my code below:
void MCU_sleep (void)
{
UART1_send_array ((u8 *)''go to sleep\r\n'', 13); //debug
AFIO -> EXTICR[0] = 0 << 12; //exit_lin3 enable
AFIO -> EXTICR[2] = 0 << 0; //exit_lin8 enable
EXTI -> IMR = (1 << 3) | (1 << 8); //exit interrupt mode
EXTI -> FTSR = (1 << 3) | (1 << 8); //rising edge trigger
//clr pending request and rtc flag before enter stop
EXTI -> PR = (1 << 3) | (1 << 8);
RTC -> CRL &= (~(1 << 1)); //clr RTC alarm flag
//set SLEEP_DEEP bit(2), clr SEVEONPEND bit(4)
SCB -> SCR |= (1 << 2);
//clr PDDS bits in PWR_CR, means sleep mode
PWR -> CR &= (~(1 << 1));
//LPDS(bit0) = 0
PWR -> CR &= (~(1 << 0)); //regulator on during sleep mode
WFI_SET();
//clr SLEEP_DEEP bit after wakeup
SCB -> SCR &= (~((1 << 2)));
RTC -> CRL &= (~(1 << 1));
//after wakeup, configure clock again
RCC_config ();
UART1_send_array ((u8 *)''wake up\r\n'', 9);
}
void interrupt_config (void)
{
//EXIT3, position 9?priority 16
//EXIT8?position 23? priority 30
//ISER?interrupt enable
NVIC -> ISER[0] = (1 << 9) | (1 << 23);
}
the debug information by uart descrip below:
power on
RCC_CSR=0x0C000000
UART1 test
go to sleep //mcu sleep here, and I press button, mcu reset,
power on
RCC_CSR=0x0C000000
UART1 test
go to sleep
#forum-says-no #stm32-stop-mode-reset
