Posted on October 16, 2015 at 11:31Good day,
I use CooCox 1.7.8 and STM32F4DISCOVERY as programmator.
Problem is, that after re-configuring SysClk to PLL running on 168MHz
(which is confirmed through observing 84MHz on MCO1 output) ToggleBit
command produce no effect on LED's. If decrease SysClk to 42MHz, everything is working.
Please see code below:
***
#include ''stm32f4xx.h''
#include ''stm32f4xx_gpio.h'' </p>
</b>
#include ''stm32f4xx_rcc.h''
GPIO_InitTypeDef
GPIO_InitStruct; int i, k=0, l=0; </p>
</b>
int
main(
void
) {
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE,
ENABLE
); GPIO_InitStruct.
GPIO_Pin
= GPIO_Pin_8|GPIO_Pin_10;
// we want to configure LED's: D1, D3
GPIO_InitStruct.
GPIO_Mode
=
GPIO_Mode_OUT
;
// we want it to be an Output
GPIO_InitStruct.
GPIO_Speed
=
GPIO_Speed_100MHz
;
//this sets the GPIO modules clock speed
GPIO_InitStruct.
GPIO_OType
=
GPIO_OType_PP
;
// this sets the pin type to push / pull (as opposed to open drain)
GPIO_InitStruct.
GPIO_PuPd
=
GPIO_PuPd_NOPULL
;
// this disables the pull-down resistor GPIO_Init(GPIOE, &GPIO_InitStruct);
GPIO_SetBits(GPIOE, GPIO_Pin_8|GPIO_Pin_10);
// LED1, LED3 On
for
(i=0; i<50000; i++);
//Wait
GPIO_ResetBits(GPIOE, GPIO_Pin_8|GPIO_Pin_10);
// LED1, LED3 Off /* Output HSE clock on MCO1 pin(PA8) ****************************************/
/* Enable the GPIOA peripheral */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,
ENABLE
); /* Configure MCO1 pin(PA8) in alternate function */
GPIO_InitStruct.
GPIO_Pin
= GPIO_Pin_8; GPIO_InitStruct.
GPIO_Speed
=
GPIO_Speed_100MHz
; GPIO_InitStruct.
GPIO_Mode
=
GPIO_Mode_AF
; GPIO_InitStruct.
GPIO_OType
=
GPIO_OType_PP
; GPIO_InitStruct.
GPIO_PuPd
=
GPIO_PuPd_UP
; GPIO_Init(GPIOA, &GPIO_InitStruct);
/* (PLL_clock/2) selected to output on MCO1 pin (PA8)*/
RCC_MCO1Config(RCC_MCO1Source_PLLCLK, RCC_MCO1Div_2);
RCC_PLLConfig(RCC_PLLSource_HSI, 0x08, 0xA8, 0x02, 0x07);
//PLLM=8 (2MHz), PLLN=168 (336MHz), PLLP=2 (SYS=168), PLLQ=7 (USB=48)
RCC_PLLCmd(
ENABLE
);
//Enable PLL using HSI
while
(!RCC_GetFlagStatus(RCC_FLAG_PLLRDY));
//Wait till PLL frequency established (23) RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
//Choose PLL as SYSCLK
for
(i=0; i<16800; i++);
//Wait
while
(1) {
GPIO_ToggleBits(GPIOE, GPIO_Pin_8|GPIO_Pin_10);
// LED1, LED3 On
for
(i=0; i<1680; i++);
//Wait GPIO_ToggleBits(GPIOE, GPIO_Pin_8|GPIO_Pin_10);
// LED1, LED3 On
for
(i=0; i<1680; i++);
//Wait }
***
As well, under debugger last while(1) reach its end successfully
(using breakpoints) but after it hangs.
Thanks in advance,
Konstantin
