STM32F407 TIM8互补

Question

I can't figure out why my code doesn't work! I've worked with TIM1 and everything works fine but when I change to TIM8, PC6 and PC7 are always on and the complementaries always off. Please help me out and happy holidays!

/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_tim.h"
#include "misc.h"

/* Private typedef -----------------------------------------------------------*/
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_OCInitTypeDef  TIM_OCInitStructure;
TIM_BDTRInitTypeDef TIM_BDTRInitStructure;

/* Private define ------------------------------------------------------------*/
#define frequency 42500 /* output frequency 42500 KHz */
#define f1 1/2 /* phase shift 90 degrees */

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
int TimerPeriod = 0;

/* Private function prototypes -----------------------------------------------*/
void TIM_Config(void);

/* Private functions ---------------------------------------------------------*/

/**
  * Main program
  */
int main(void)
{

  /* TIM8 Configuration */
  TIM_Config();

  /* Compute the value to be set in ARR register to generate the desired signal frequency */
  TimerPeriod = ((SystemCoreClock/2) / frequency) - 1;

  /* Time Base configuration */
  TIM_TimeBaseStructure.TIM_Prescaler = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = TimerPeriod;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;

  TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);

  /* Channel 1 and 2 Configuration in Toggle mode */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
  TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
  TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
  TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;

  TIM_OCInitStructure.TIM_Pulse = (TimerPeriod/6)+ (TimerPeriod * f1);
  TIM_OC1Init(TIM8, &TIM_OCInitStructure);

  TIM_OCInitStructure.TIM_Pulse = (TimerPeriod/6) ;
  TIM_OC2Init(TIM8, &TIM_OCInitStructure);

  /* Automatic Output enable, Break, dead time and lock configuration*/
  TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
  TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
  TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_1;
  TIM_BDTRInitStructure.TIM_DeadTime = 25; ///////// the right value for 250ns delay ////////
  TIM_BDTRInitStructure.TIM_Break = TIM_Break_Enable;
  TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
  TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;

  TIM_BDTRConfig(TIM8, &TIM_BDTRInitStructure);

  /* TIM8 counter enable */
  TIM_Cmd(TIM8, ENABLE);

  /* Main Output Enable */
  TIM_CtrlPWMOutputs(TIM8, ENABLE);

  while (1)
  {
  }
}

/**
  *  Configure the TIM8 Pins.
  */
void TIM_Config(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;

  /* GPIOA, GPIOB and GPIOC clocks enable */
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB | RCC_AHB1Periph_GPIOC, ENABLE);

  /* TIM8 clock enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);

  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_NOPULL;

  /*GPIOA Configuration: Channel 1N and BKIN as alternate function push-pull*/
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  /* GPIOA Configuration: Channel 1 and 2 as alternate function push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_Init(GPIOC, &GPIO_InitStructure);

  /* GPIOB Configuration: Channel 2N as alternate function push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  /* Connect TIM pins to AF1 */
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_TIM8);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_TIM8);
  GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_TIM8);
  GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_TIM8);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource0, GPIO_AF_TIM8);

}

Answer 1

@Swanand try to change this

TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Set;

and let me know.