Posted on May 17, 2011 at 13:59This worked for Timer1. Do you need to use function, TIM_CtrlPWMOutputs(TIMx, ENABLE) ?
John F.
#include ''stm32f10x.h''
void RCC_Configuration(void);
void GPIO_Configuration(void);
void Timer1_Configuration(void);
//note with SYSCLK_FREQ_72MHz defined, PCLK1 = 36MHz and PCLK2 = 72MHz
uint16_t CCR1_Val = 1000; //1500 = 1.5ms (1000 = 1ms, 2000 = 2ms);
int main(void)
{
RCC_Configuration();
GPIO_Configuration();
Timer1_Configuration();
while(1)
{
GPIO_WriteBit(GPIOB, GPIO_Pin_0, Bit_SET);
GPIO_WriteBit(GPIOB, GPIO_Pin_0, Bit_RESET);
}
}
void RCC_Configuration(void)
{
//Setup the microcontroller system. Initialize the Embedded Flash Interface,
//initialize the PLL and update the SystemFrequency variable.
SystemInit();
// Enable GPIOB, AFIO and Timer1 clocks
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO | RCC_APB2Periph_TIM1, ENABLE);
}
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
//partial remap of Timer1
GPIO_PinRemapConfig(GPIO_PartialRemap_TIM1, ENABLE);
//GPIOB Configuration: TIM1 channel 2N as alternate function push-pull
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}
void Timer1_Configuration(void)
{
//Timer1 is clocked by PCLK2 = 72MHz
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_DeInit(TIM1);
//Time base configuration
TIM_TimeBaseStructure.TIM_Prescaler = 71; //clocked at 72MHz / 72 = 1MHz
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseStructure.TIM_Period = 19999; //period = (72MHz / 72) / 20000 = 50Hz (20ms period)
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
/* Channel 1 Configuration in PWM mode */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_Pulse = CCR1_Val;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_Low;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
TIM_OC2Init(TIM1, &TIM_OCInitStructure);
TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);
TIM_CtrlPWMOutputs(TIM1, ENABLE);
//TIM1 enable counter
TIM_Cmd(TIM1, ENABLE);
}
