STM32f103-I am try to blinking led through timer1 with 50% duty cycle

[nirmalmallick0]

Posted on November 08, 2014 at 08:17

Dear frnd,

    i am recently started using this micro and iar.so plz help me 

How to blinking my led though timer1 and 50% duty cycle...the led is connected to PA8 pin of the micro please share any progrram..

[Tesla DeLorean]

Posted on November 08, 2014 at 15:19

I'll try to dig up a better example, but try this thread

https://my.st.com/public/STe2ecommunities/mcu/Lists/STM32Discovery/Flat.aspx?RootFolder=https://my.st.com/public/STe2ecommunities/mcu/Lists/STM32Discovery/Example%20PWM%20on%20STM32-Discovery%20Blue%20LED&FolderCTID=0x01200200770978C69A1141439FE559EB459D75800084C20D8867EAD444A5987D47BE638E0F&currentviews=10745

Where Period = N-1, Pulse = N/2 for 50%

[Tesla DeLorean]

Posted on November 08, 2014 at 17:23

A quick blind port

// STM32F1xx TIM1_CH1 (PA8) PWM1 1Hz 50/50 Duty - [e-mail]
#include ''stm32f10x.h''
int main(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
uint32_t Prescaler, Period;
/*!< 
At
this stage the microcontroller clock setting is already configured,
this is done through SystemInit() function which is called from startup
file (startup_stm32f10x_xx.s) before to branch to application main.
To reconfigure the default setting of SystemInit() function, refer to
system_stm32f10x.c file
*/
/* Enable GPIO clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
/* Enable TIM clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
/* Configure TIM1_CH1 as alternate function push-pull */
GPIO_InitStructure.GPIO_Mode
= 
GPIO_Mode_AF_PP
;
GPIO_InitStructure.GPIO_Pin
= 
GPIO_Pin_8
;
GPIO_InitStructure.GPIO_Speed
= 
GPIO_Speed_2MHz
; // No point in overdriving
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Both these must ultimately fit in 16-bit, ie 1..65536 */
Prescaler = (SystemCoreClock / 20000); // System -> 20 KHz
Period = 20000; // 20 KHz -> 1 Hz
/* Extra caution required with TIM1/TIM8 full function timers, to initialize ALL fields */
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Prescaler = (uint16_t)(Prescaler - 1);
TIM_TimeBaseStructure.TIM_Period = (uint16_t)(Period - 1);
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; // Where do those stairs go? They go up!
TIM_TimeBaseStructure.TIM_ClockDivision = 0; // Not used
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0; // Not used
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
/* PWM1 Mode configuration: Channel1 */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_Pulse = (uint16_t)(Period / 2); // 50%
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
/* TIM1 enable counter */
TIM_Cmd(TIM1, ENABLE);
/* TIM1 Main Output Enable */
TIM_CtrlPWMOutputs(TIM1, ENABLE);
/* Infinite loop */
while(1);
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t* file, uint32_t line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf(''Wrong parameters value: file %s on line %d

'', file, line) */
/* Infinite loop */
while (1)
{
}
}
#endif