基于stm32f103zet6芯片编写通过PWM输出50%占空比控制L298n模块的程序

好的，以下是基于STM32F103ZET6芯片编写通过PWM输出50%占空比控制L298N模块的程序：

#include "stm32f10x.h"

void GPIO_Configuration(void);
void PWM_Configuration(void);

int main(void)
{
    GPIO_Configuration();
    PWM_Configuration();

    while(1);

    return 0;
}

void GPIO_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
}

void PWM_Configuration(void)
{
    TIM_OCInitTypeDef TIM_OCInitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

    TIM_TimeBaseStructure.TIM_Period = 999;
    TIM_TimeBaseStructure.TIM_Prescaler = 71;
    TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = 499;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC2Init(TIM3, &TIM_OCInitStructure);
    TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable);

    TIM_Cmd(TIM3, ENABLE);
}

上面是一个简单的程序，其中`GPIO_Configuration()`函数配置了`PA8`和`PA9`两个引脚为复用推挽输出模式，`PWM_Configuration()`函数配置了定时器`TIM3`为PWM1模式，频率为72M/72/1000=1kHz，占空比为50%。这样就可以控制L298N模块的输出了。