并且点亮 板上的 LD1,LD2 灯闪烁。
void
STM32_PWM_GPIO_Configuration(void)
{
// 11：完全映像
STM32_Afio_Regs->mapr.bit.TIM3_REMAP=3;
// LD1 =P7 LD2=PC6
STM32_Gpioc_Regs->crl.bit.CNF6=Output_Af_push_pull; // PC.06 复用功能推挽输出模式
STM32_Gpioc_Regs->crl.bit.MODE6=Output_Mode_50mhz; // PC.06 输出模式，最大速度50MHz
STM32_Gpioc_Regs->crl.bit.CNF7=Output_Af_push_pull; // PC.07 复用功能推挽输出模式
STM32_Gpioc_Regs->crl.bit.MODE7=Output_Mode_50mhz; // PC.07 输出模式，最大速度50MHz
}//end sub
void
STM32_TIM3_Configuration(void)
{
// TIM_DeInit( TIM3);//复位TIM3定时器
STM32_Rcc_Regs->apb1rstr.all |= RCC_TIM3RST;
STM32_Rcc_Regs->apb1rstr.all &= ~RCC_TIM3RST;
//时钟使能
STM32_Rcc_Regs->apb1enr.all |=RCC_TIM3EN;
//TIM_TimeBaseStructure.TIM_Period = 9999;
//TIM_TimeBaseStructure.TIM_Prescaler = 7200;
//TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
//TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
//TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
STM32_Tim3_Regs->arr.all=9999; // 定时周期，PWM频率！ 10毫秒*100=1秒
STM32_Tim3_Regs->psc.all=720; // 7200分频 72MHZ/72,00 72,000,000/72,00=10,000
STM32_Tim3_Regs->cr1.bit.CKD=0; // 时钟分频因子
STM32_Tim3_Regs->cr1.bit.DIR=0; // 0：计数器向上计数
//TIM_ClearFlag(TIM3, TIM_FLAG_Update);
STM32_Tim3_Regs->sr.bit.UIF=0; //更新中断标记由软件清0 ,例如当上溢或下溢时,软件对CNT重新初始化
//TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
//TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
//TIM_OCInitStructure.TIM_Pulse = CCR1_Val;
//TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
//TIM_OC1Init(TIM3, &TIM_OCInitStructure);
// timer3 的 通道1 是 PC6 引脚, AFIO完全映射
STM32_Tim3_Regs->ccer.bit.CC1P=0; // 输入/捕获1输出极性 0：OC1高电平有效 1：OC1低电平有效
STM32_Tim3_Regs->ccer.bit.CC1E=1; // 输入/捕获1输出使能 1： 开启－ OC1信号输出到对应的输出引脚。
STM32_Tim3_Regs->ccer.bit.CC2P=0; // 输入/捕获2输出极性 0：OC1高电平有效 1：OC1低电平有效
STM32_Tim3_Regs->ccer.bit.CC2E=1; // 输入/捕获2输出使能 1： 开启－ OC2信号输出到对应的输出引脚。
STM32_Tim3_Regs->ccmr1.ou_bit.CC1S=0;//00：输出比较1 通道1 被配置为输出
STM32_Tim3_Regs->ccmr1.ou_bit.CC2S=0;//00：输出比较2 通道2 被配置为输出
STM32_Tim3_Regs->ccmr1.ou_bit.OC1M=6;//0110：PWM模式1
STM32_Tim3_Regs->ccmr1.ou_bit.OC2M=6;//0110：PWM模式1
STM32_Tim3_Regs->ccr1.all=5000;// 占空比 50％
STM32_Tim3_Regs->ccr2.all=1000;// 10％
// TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);
STM32_Tim3_Regs->ccmr1.ou_bit.OC1PE=1; //OC1PE：输出比较1预装载使能1：开启TIMx_CCR1寄存器的预装载功能
STM32_Tim3_Regs->ccmr1.ou_bit.OC2PE=1; //OC1PE：输出比较2预装载使能1：开启TIMx_CCR2寄存器的预装载功能
//TIM_ARRPreloadConfig(TIM3, ENABLE);
STM32_Tim3_Regs->cr1.bit.ARPE=1; // 7 自动重装载预装载允许位 0：TIM1_ARR寄存器没有缓冲
// TIM3 enable counter
//TIM_Cmd(TIM3, ENABLE);
STM32_Tim3_Regs->cr1.bit.CEN=1;// 开启计数器
STM32_Tim3_Regs->egr.bit.UG=1; //触发一次事件中断。
STM32_Tim3_Regs->sr.bit.UIF=0;
}//end sub
九九版:
这个是STM32的PWM输出模式，STM32的TIM1模块是增强型的定时器模块，天生就是为电机控制而生，可以产生3组6路PWM，同时每组2路PWM为互补，并可以带有死区，可以用来驱动H桥。
下面的代码，是利用TIM1模块的1、2通道产生一共4路PWM的代码例子，类似代码也可以参考ST的固件库中相应example
//Step1.开启TIM和相应端口时钟
//启动GPIO
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | \
RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOD,\
ENABLE);
//启动AFIO
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
//启动TIM1
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
//Step2. GPIO做相应设置，为AF输出
//PA.8/9口设置为TIM1的OC1输出口
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);
//PB.13/14口设置为TIM1_CH1N和TIM1_CH2N输出口
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_14;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
//Step3. TIM模块初始化
void TIM_Configuration(void)
{
TIM_TimeBaseInitTypeDef TIM_BaseInitStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
//TIM1基本计数器设置（设置PWM频率）
//频率=TIM1_CLK/(ARR+1)
TIM_BaseInitStructure.TIM_Period = 1000-1;
TIM_BaseInitStructure.TIM_Prescaler = 72-1;
TIM_BaseInitStructure.TIM_ClockDivision = 0;
TIM_BaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_BaseInitStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit(TIM1, &TIM_BaseInitStructure);
//启用ARR的影子寄存器（直到产生更新事件才更改设置）
TIM_ARRPreloadConfig(TIM1, ENABLE);
//TIM1_OC1模块设置（设置1通道占空比）
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
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_Pulse = 120;
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
//启用CCR1寄存器的影子寄存器（直到产生更新事件才更改设置）
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);
//TIM2_OC2模块设置（设置2通道占空比）
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_Pulse = 680;
TIM_OC2Init(TIM1, &TIM_OCInitStructure);
//启用CCR2寄存器的影子寄存器（直到产生更新事件才更改设置）
TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);
//死区设置
TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
TIM_BDTRInitStructure.TIM_DeadTime = 0x90; //这里调整死区大小0-0xff
TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);
//TIM1开启
TIM_Cmd(TIM1, ENABLE);
//TIM1_OC通道输出PWM（一定要加）
TIM_CtrlPWMOutputs(TIM1, ENABLE);
}
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