我是 stm32f407 发现板的新手，我正在尝试制作 4 个可以控制相移和占空比的信号。问题是，当我将定时器设置为 PWM 模式时，我无法控制通道_1 和通道_2 之间的相移。我知道我必须使用中断，但我不知道我应该在其中编写什么代码。如果你能帮助我，我将不胜感激。
这是我的代码，我使用一个中断每隔一段时间打开/关闭一个 LED（延迟还没有很好地同步）。
/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "misc.h"
#include "stm32f4xx_tim.h"
#include "stm32f4xx_usart.h"
#include "delay.h"
/* Private typedef -----------------------------------------------------------*/
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
/* Private define ------------------------------------------------------------*/
#define frequency 42500
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
int Prescaler = 0;
int Period = 84000000 / frequency; // ~42.5KHz
int pulse_width;
/* Private function prototypes -----------------------------------------------*/
void GPIO_Config(void);
void PWM_Config(void);
void PWM_SetDC(int channel,int dutycycle);
void Delay(__IO int nCount);
void LED_Config(void);
/* Private functions ---------------------------------------------------------*/
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)
{
Delay(10000000);
GPIO_ToggleBits(GPIOD, GPIO_Pin_15);
TIM_ClearITPendingBit(TIM2, TIM_IT_CC1);
}
}
/**
* Main program
*/
int main(void)
{
/* GPIO Configuration */
GPIO_Config();
LED_Config();
/* PWM Configuration */
PWM_Config();
PWM_SetDC(1,80);
PWM_SetDC(2,40);
PWM_SetDC(3,0);
PWM_SetDC(4,0);
while (1)
{
}
}
/**
* Configure the TIM2 Output Channels.
*/
void GPIO_Config(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable the TIM2 global Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* TIM2 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
/* GPIOA clock enable */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA , ENABLE);
GPIO_InitTypeDef GPIO_InitStructure;
/* GPIOC Configuration: TIM2 CH1 (PA0), TIM2 CH2 (PA1), TIM2 CH3 (PA2), TIM2 CH4 (PA3) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Connect TIM2 pins to AF2 */
GPIO_PinAFConfig(GPIOA, GPIO_PinSource0, GPIO_AF_TIM2);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource1, GPIO_AF_TIM2);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_TIM2);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource3, GPIO_AF_TIM2);
}
void PWM_Config(void)
{
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = Period - 1;
TIM_TimeBaseStructure.TIM_Prescaler = 0;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_ARRPreloadConfig(TIM2, ENABLE);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
/* PWM1 Mode configuration: Channel1 */
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OC1Init(TIM2, &TIM_OCInitStructure);
TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);
////////////////////////* TIM INTERRUPT enable *////////////////////////////
TIM_ITConfig(TIM2, TIM_IT_CC1, ENABLE);
////////////////////////////////////////////////////////////////////////////
/* PWM1 Mode configuration: Channel2 */
// TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OC2Init(TIM2, &TIM_OCInitStructure);
TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable);
/* PWM1 Mode configuration: Channel3 */
// TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OC3Init(TIM2, &TIM_OCInitStructure);
TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Enable);
/* PWM1 Mode configuration: Channel4 */
// TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OC4Init(TIM2, &TIM_OCInitStructure);
TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable);
/* TIM2 enable counter */
TIM_Cmd(TIM2, ENABLE);
}
void PWM_SetDC(int channel,int dutycycle)
{
if (dutycycle <= 100 && dutycycle >= 0)
{
pulse_width=(Period*dutycycle)/100;
if (channel == 1)
{
TIM2->CCR1 = pulse_width;
}
else if (channel == 2)
{
TIM2->CCR2 = pulse_width;
}
else if (channel == 3)
{
TIM2->CCR3 = pulse_width;
}
else
{
TIM2->CCR4 = pulse_width;
}
}
}
void LED_Config(void)
{
/* GPIOD Peripheral clock enable */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
/* Configure PD12, PD13, PD14 and PD15 in output push-pull mode */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13| GPIO_Pin_14| GPIO_Pin_15;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOD, &GPIO_InitStructure);
}
/* Delay Function.
* nCount:specifies the Delay time length.
*/
void Delay(__IO int nCount)
{
while(nCount--)
{
}
}