STM32f103Z,无法输出PWM波

HelloWinter · 发表于 2016-10-17 21:39:50

如题，刚刚接触单片机，用的是STM32f103Z的板子，想通过控制占空比，输出PWM波，但是没能完成。各位前辈能不能帮我看看哪里出了问题？新人第一次发帖，如果有什么不对的地方，希望大家指出，先谢过各位前辈了。
下面是我用到的程序。
#include "main.h"

int main(void)
{

static uint16_t k=0;

PWM_Configuration();

while(1)
{
delay_ms(20);

if(k==0)
      PWM1=1000;
if(k==1)
PWM1=2000;
}
}
#include "main.h"

//PA8----EN
//PA9----PWM---TIM1_CH2
//PA10---EN
//PA11---PWM---TIM1_CH4

void PWM_Configuration(void)
{
TIM_TimeBaseInitTypeDef  tim;
TIM_OCInitTypeDef       oc;
GPIO_InitTypeDef       gpio;

RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOA |
                        RCC_APB2Periph_TIM1, ENABLE);

   gpio.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_11;
gpio.GPIO_Mode = GPIO_Mode_AF_PP;
gpio.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &gpio);

gpio.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_10;
gpio.GPIO_Mode = GPIO_Mode_Out_PP;
gpio.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &gpio);

GPIO_SetBits(GPIOA,GPIO_Pin_8 | GPIO_Pin_10);

tim.TIM_Period=5000;
tim.TIM_Prescaler=36-1;
tim.TIM_ClockDivision=TIM_CKD_DIV1;
tim.TIM_CounterMode=TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &tim);

oc.TIM_OCMode = TIM_OCMode_PWM2;
oc.TIM_OutputState = TIM_OutputState_Enable;
oc.TIM_OutputNState = TIM_OutputNState_Disable;
oc.TIM_Pulse = 0;
oc.TIM_OCPolarity = TIM_OCPolarity_Low;
oc.TIM_OCNPolarity = TIM_OCPolarity_High;
oc.TIM_OCIdleState = TIM_OCIdleState_Reset;
oc.TIM_OCNIdleState = TIM_OCIdleState_Reset;
TIM_OC2Init(TIM1, &oc);
TIM_OC4Init(TIM1, &oc);

TIM_ARRPreloadConfig(TIM1, ENABLE);

TIM_CtrlPWMOutputs(TIM1,ENABLE);

TIM_Cmd(TIM1, ENABLE);
}

#ifndef __PWM_H__
#define __PWM_H__

void PWM_Configuration(void);
#define PWM1 TIM1->CCR1

#endif