/*
* * 软件功用: PWM输出实验* */#include "stm32f10x.h"#include "delay.h"void RCC_Configuration(void);void GPIO_Configuration(void);void NVIC_Configuration(void);void TIM3_Configuration(u16 arr,u16 psc);/*函数: int main(void)功用: main主函数参数: 无回来: 无/int main(void){u8 led_direction=1;u16 led_brightness=0;RCC_Configuration();GPIO_Configuration();TIM3_Configuration(499,71); delay_init(72);GPIO_ResetBits(GPIOB,GPIO_Pin_5); while(1){delay_ms(10);if(1==led_direction) led_brightness++;else led_brightness--;if(led_brightness>499) led_direction=0;if(led_brightness==0) led_direction=1;TIM_SetCompare2(TIM3, led_brightness);} }/*函数: void RCC_Configuration(void)功用: 复位和时钟操控 装备参数: 无回来: 无/void RCC_Configuration(void){ErrorStatus HSEStartUpStatus; //界说外部高速晶体发动状况枚举变量RCC_DeInit(); //复位RCC外部设备寄存器到默认值RCC_HSEConfig(RCC_HSE_ON); //翻开外部高速晶振HSEStartUpStatus = RCC_WaitForHSEStartUp(); //等候外部高速时钟准备好if(HSEStartUpStatus == SUCCESS) //外部高速时钟现已准别好{FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable); //舱位FLASH预读缓冲功用,加快FLASH的读取。一切程序中有必要的用法.方位:RCC初始化子函数晒干,时钟起振之后FLASH_SetLatency(FLASH_Latency_2); //flash操作的延时RCC_HCLKConfig(RCC_SYSCLK_Div1); //装备AHB(HCLK)时钟等于==SYSCLKRCC_PCLK2Config(RCC_HCLK_Div1); //装备APB2(PCLK2)钟==AHB时钟RCC_PCLK1Config(RCC_HCLK_Div2); //装备APB1(PCLK1)钟==AHB1/2时钟RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9); //装备PLL时钟 == 外部高速晶体时钟 * 9 = 72MHzRCC_PLLCmd(ENABLE); //使能PLL时钟while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET) //等候PLL时钟安排妥当{}RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK); //装备体系时钟 = PLL时钟while(RCC_GetSYSCLKSource() != 0x08) //查看PLL时钟是否作为体系时钟{}}RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE); //答应 GPIOB、AFIO端口复用时钟RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能}/*函数: void GPIO_Configuration(void)功用: GPIO装备参数: 无回来: 无/void GPIO_Configuration(void){GPIO_InitTypeDef GPIO_InitStructure; //界说GPIO初始化结构体GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;//复用输出 GPIO_Init(GPIOB, &GPIO_InitStructure); //PB用于输出操控LED灯}void TIM3_Configuration(u16 arr,u16 psc) //TIM3定时器装备 {TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;TIM_OCInitTypeDef TIM_OCInitStructure;GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3,ENABLE);//端口映射,参阅STM32中文手册P119和库函数手册P132 PB4TIM_TimeBaseStructure.TIM_Period = arr; //设置鄙人一个更新事情装入活动的主动重装载寄存器周期的值 TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟切割:TDTS = Tck_timTIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式TIM_TimeBaseInit(TIM3, & TIM_TimeBaseStructure); //依据指定的参数初始化TIMx的时刻基数单位//((1+71[TIM_Prescaler] )/72M)*(1+499[TIM_Period] )=500us /* Configures the TIM3 in PWM Mode */TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;TIM_OC2Init(TIM3, & TIM_OCInitStructure); //此处用比较 2 寄存器,对应main函数 ,也可设置为 比较 1 寄存器TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable); //预装载器使能//ARR预装载缓冲器使能 TIM_ARRPreloadConfig(TIM3, ENABLE);TIM_Cmd(TIM3, ENABLE); //使能TIMx}