stm32单片机芯片产生PWM波的源程序(Keil)
GPIO寄存器描述
1、端口配置低寄存器(GPIOx_CRL)(x = A...E)
2、端口配置高寄存器(GPIOx_CRH)(x = A...E)
3、端口输入数据寄存器(GPIOx_IDR)(x = A...E)
这些位为只读并只能以字(16位)的形式读出。读出的值为对应I/O口的状态。
4、端口输出数据寄存器(GPIOx_ODR)(x = A...E)
只能以字(16bit)的形式操作,复位值全是0。写0即输出0,写1即输出1。
5、端口位设置/清除寄存器(GPIOx_BSRR)(x = A...E)
高16bit写1用于清0,低16bit写1用于置位,同时写1的话低16bi有效。
6、端口位清除寄存器(GPIOx_BRR)(x = A...E)
低16位写1用于置位。
7、端口配置锁定寄存器(GPIOx_LCKR)(x = A...E)
全部资料下载地址:
PWM_Output.rar
(4.08 MB, 下载次数: 37)
- /**
- ******************************************************************************
- * @file bsp_pwm_output.c
- * @author STMicroelectronics
- * @version V1.0
- * @date 2013-xx-xx
- * @brief tim3输出四路pwm bsp
- ******************************************************************************
- * @attention
- ******************************************************************************
- */
-
- #include "bsp_pwm_output.h"
- /**
- * @brief 配置TIM3复用输出PWM时用到的I/O
- * @param 无
- * @retval 无
- */
- static void TIMx_GPIO_Config(void)
- {
- GPIO_InitTypeDef GPIO_InitStructure;
- /* 设置TIM3CLK 为 72MHZ */
- // RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
- macTIM_APBxClock_FUN (macTIM_CLK, ENABLE);
- /* GPIOA and GPIOB clock enable */
- macTIM_GPIO_APBxClock_FUN (macTIM_GPIO_CLK, ENABLE);
- /*GPIOA Configuration: TIM3 channel 1 as alternate function push-pull */
- GPIO_InitStructure.GPIO_Pin = macTIM_CH1_PIN;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; // 复用推挽输出
- GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
- GPIO_Init(macTIM_CH1_PORT, &GPIO_InitStructure);
- /*GPIOB Configuration: TIM3 channel 2 as alternate function push-pull */
- GPIO_InitStructure.GPIO_Pin = macTIM_CH2_PIN;
- GPIO_Init(macTIM_CH2_PORT, &GPIO_InitStructure);
- /*GPIOB Configuration: TIM3 channel 3 as alternate function push-pull */
- GPIO_InitStructure.GPIO_Pin = macTIM_CH3_PIN;
- GPIO_Init(macTIM_CH3_PORT, &GPIO_InitStructure);
-
- /*GPIOB Configuration: TIM3 channel 4 as alternate function push-pull */
- GPIO_InitStructure.GPIO_Pin = macTIM_CH4_PIN;
- GPIO_Init(macTIM_CH4_PORT, &GPIO_InitStructure);
-
- }
- /**
- * @brief 配置TIM3输出的PWM信号的模式,如周期、极性、占空比
- * @param 无
- * @retval 无
- */
- /*
- * TIMxCLK/CK_PSC --> TIMxCNT --> TIMx_ARR --> TIMxCNT 重新计数
- * TIMx_CCR(电平发生变化)
- * 信号周期=(TIMx_ARR +1 ) * 时钟周期
- * 占空比=TIMx_CCR/(TIMx_ARR +1)
- */
- static void TIMx_Mode_Config(void)
- {
- TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
- TIM_OCInitTypeDef TIM_OCInitStructure;
- /* PWM信号电平跳变值 */
- u16 CCR1_Val = 160;
- u16 CCR2_Val = 0;
- u16 CCR3_Val = 0;
- u16 CCR4_Val = 0;
- /* -----------------------------------------------------------------------
- macTIMx Channel1 duty cycle = (macTIMx_CCR1/ macTIMx_ARR+1)* 100% = 50%
- macTIMx Channel2 duty cycle = (macTIMx_CCR2/ macTIMx_ARR+1)* 100% = 37.5%
- macTIMx Channel3 duty cycle = (macTIMx_CCR3/ macTIMx_ARR+1)* 100% = 25%
- macTIMx Channel4 duty cycle = (macTIMx_CCR4/ macTIMx_ARR+1)* 100% = 12.5%
- ----------------------------------------------------------------------- */
- /* Time base configuration */
- TIM_TimeBaseStructure.TIM_Period = 999; //当定时器从0计数到999,即为1000次,为一个定时周期
- TIM_TimeBaseStructure.TIM_Prescaler = 0; //设置预分频:不预分频,即为72MHz
- TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1 ; //设置时钟分频系数:不分频(这里用不到)
- TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数模式
- TIM_TimeBaseInit(macTIMx, &TIM_TimeBaseStructure);
- /* PWM1 Mode configuration: Channel1 */
- TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //配置为PWM模式1
- TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
- TIM_OCInitStructure.TIM_Pulse = CCR1_Val; //设置跳变值,当计数器计数到这个值时,电平发生跳变
- TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //当定时器计数值小于CCR1_Val时为高电平
- TIM_OC1Init(macTIMx, &TIM_OCInitStructure); //使能通道1
- TIM_OC1PreloadConfig(macTIMx, TIM_OCPreload_Enable);
- /* PWM1 Mode configuration: Channel2 */
- TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
- TIM_OCInitStructure.TIM_Pulse = CCR2_Val; //设置通道2的电平跳变值,输出另外一个占空比的PWM
- TIM_OC2Init(macTIMx, &TIM_OCInitStructure); //使能通道2
- TIM_OC2PreloadConfig(macTIMx, TIM_OCPreload_Enable);
- /* PWM1 Mode configuration: Channel3 */
- TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
- TIM_OCInitStructure.TIM_Pulse = CCR3_Val; //设置通道3的电平跳变值,输出另外一个占空比的PWM
- TIM_OC3Init(macTIMx, &TIM_OCInitStructure); //使能通道3
- TIM_OC3PreloadConfig(macTIMx, TIM_OCPreload_Enable);
- /* PWM1 Mode configuration: Channel4 */
- TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
- TIM_OCInitStructure.TIM_Pulse = CCR4_Val; //设置通道4的电平跳变值,输出另外一个占空比的PWM
- TIM_OC4Init(macTIMx, &TIM_OCInitStructure); //使能通道4
- TIM_OC4PreloadConfig(macTIMx, TIM_OCPreload_Enable);
- TIM_ARRPreloadConfig(macTIMx, ENABLE); // 使能TIM3重载寄存器ARR
- /* TIM3 enable counter */
- TIM_Cmd(macTIMx, ENABLE); //使能定时器3
- }
- /**
- * @brief TIM3 输出PWM信号初始化,只要调用这个函数
- * TIM3的四个通道就会有PWM信号输出
- * @param 无
- * @retval 无
- */
- void TIMx_PWM_Init(void)
- {
- TIMx_GPIO_Config();
- TIMx_Mode_Config();
- }
- /*********************************************END OF FILE**********************/
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