STM32f303 Output Compare

arganasss · ‎2014-05-09

Posted on May 09, 2014 at 15:48

Hello, i'd like to do output compare on four pins: PE13, PE9 (LEDS), PA10 and PA12. Everyone works except PA12. I tried to do that with TIM16 and TIM4 with no luck. And i reconfigured the channels, i understand how they are mapped to pins (datasheet). So maybe someone knows why this happens? Here is the code. Thanks for your help.

#include ''stm32f30x.h''

TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;

TIM_OCInitTypeDef TIM_OCInitStructure;

GPIO_InitTypeDef GPIO_InitStructure;

void Leds_config(void);

void Timer_config(void);

int main(void)

{

// Enable clocks for E and A ports

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOE, ENABLE);

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);

Leds_config();

Timer_config();

while(1)

{

}

void Leds_config(void)

{

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_13; // use 9 and 10 pins port E

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; // use alternate-function mode

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; // High speed mode

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; // Push-pull mode

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; // don't use pull up resistors

GPIO_Init(GPIOE, &GPIO_InitStructure); // write values to E port registers

GPIO_PinAFConfig(GPIOE, GPIO_PinSource9, GPIO_AF_2); // Connect timer1 to these IO pins

GPIO_PinAFConfig(GPIOE, GPIO_PinSource13, GPIO_AF_2);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; // use 9 and 10 pins port E

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; // pin is in output mode

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; // High speed mode

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; // Push-pull mode

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; // don't use pull up resistors

GPIO_Init(GPIOA, &GPIO_InitStructure); // write values to E port

GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_10);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12; // 12 pin of PA.

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; // High speed mode

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; // Push-pull mode

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; // don't use pull up resistors

GPIO_Init(GPIOA, &GPIO_InitStructure); // write values to A port

GPIO_PinAFConfig(GPIOA, GPIO_PinSource12, GPIO_AF_10);

}

void Timer_config(void)

{

TIM_TimeBaseInitStructure.TIM_Period = 500-1; // Pulse period = 500us.

TIM_TimeBaseInitStructure.TIM_Prescaler = 72-1; // Divide timer frequency 72Mhz/72Hz gives 1us ticks.

TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up; // Count from zero to ARR value.

TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1; // Dont divide timer clock

TIM_TimeBaseInit(TIM1, &TIM_TimeBaseInitStructure);

TIM_TimeBaseInitStructure.TIM_Period = 500-1; // Pulse period = 500us.

TIM_TimeBaseInitStructure.TIM_Prescaler = 72-1; // Divide timer frequency 72Mhz/72Hz gives 1us ticks.

TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up; // Count from zero to ARR value.

TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1; // Dont divide timer clock

TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);

TIM_TimeBaseInitStructure.TIM_Period = 500-1; // Pulse period = 500us.

TIM_TimeBaseInitStructure.TIM_Prescaler = 72-1; // Divide timer frequency 72Mhz/72Hz gives 1us ticks.

TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up; // Count from zero to ARR value.

TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1; // Dont divide timer clock

TIM_TimeBaseInit(TIM4, &TIM_TimeBaseInitStructure);

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

TIM_OCInitStructure.TIM_Pulse = 350;

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

TIM_OC1Init(TIM1, &TIM_OCInitStructure);

TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable );

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

TIM_OCInitStructure.TIM_Pulse = 20;

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

TIM_OC3Init(TIM1, &TIM_OCInitStructure);

TIM_OC3PreloadConfig(TIM1, TIM_OCPreload_Enable );

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

TIM_OCInitStructure.TIM_Pulse = 350;

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

TIM_OC4Init(TIM2, &TIM_OCInitStructure);

TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable );

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

TIM_OCInitStructure.TIM_Pulse = 150;

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

TIM_OC2Init(TIM4, &TIM_OCInitStructure);

TIM_OC2PreloadConfig(TIM4, TIM_OCPreload_Enable );

TIM_CtrlPWMOutputs(TIM1, ENABLE);

TIM_CtrlPWMOutputs(TIM2, ENABLE);

TIM_CtrlPWMOutputs(TIM4, ENABLE);

TIM_Cmd(TIM1, ENABLE );

TIM_Cmd(TIM2, ENABLE );

TIM_Cmd(TIM4, ENABLE);

}

Tesla DeLorean · ‎2014-05-09

Posted on May 09, 2014 at 16:00

For the STM32F3-DISCO board observe that solder bridges SB21,22 need to be MADE for the signals PA11 & PA12 to reach the P2 header.

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arganasss · ‎2014-05-09

Posted on May 09, 2014 at 16:03

Also tried to do this on some random pins on B port and it also was successfull, so maybe PA12 or PA11 interacts with something which is not allowed or acceptable?

arganasss · ‎2014-05-09

Posted on May 09, 2014 at 16:06

Heh. My lack of experience of not knowing where to look. I was concentrating on the program so much that i didn't even think about hardware. Thanks Clive, now it works.