STM32直流电机控制程序.doc

STM32 直流减速电机控制(一) 在直流减速电机控制中，最常用的方法就是通过PWM来控制直流电机的转速。在控制小车走直线的过程中，需要两者的转速一置（如果要走得很直，还需要在短时间内保证两者的行程大致相当，这可以用PID算法来控制，以后的文章中会专门叙述）。 因此，在检测到两者转速不一样时，需要动态调整其中一个或两个轮子的PWM的点空比（简单点的就以一个轮为基准，调整另外一个轮子即可；如果以一个固定的标准的话，需要调整两个轮子的PWM占空比）。程序第一步：设置GPIO，略（输出PWM的管脚用Mode_AF_PP即可）程序第二步：设置定时器，（保证产生两路PWM即可，我用的是TIM4）void TIM4_Configuration(void)TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;TIM_OCInitTypeDef TIM_OCInitStructure;/时间基初始化TIM_TimeBaseInitStructure.TIM_Period=144; /18K/144=125Hz,这个是电机PWM的频率TIM_TimeBaseInitStructure.TIM_Prescaler=4000; /72000000/4000=18KTIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1;TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up;TIM_TimeBaseInitStructure.TIM_RepetitionCounter=0x0000;TIM_TimeBaseInit(TIM4,&TIM_TimeBaseInitStructure);/输出比较模式设置,用于4路PWM输出TIM_OCInitStructure.TIM_OCMode=TIM_OCMode_PWM2; /输出PWMTIM_OCInitStructure.TIM_OutputState=TIM_OutputState_Enable; /使能正向通道TIM_OCInitStructure.TIM_OutputNState=TIM_OutputState_Disable; /失能反向通道TIM_OCInitStructure.TIM_Pulse=PWM_L; /左轮DIR的占空比TIM_OCInitStructure.TIM_OCPolarity=TIM_OCPolarity_Low; /输出极性为低电平TIM_OCInitStructure.TIM_OCNPolarity=TIM_OCPolarity_High;/互补输出极性为高电平TIM_OCInitStructure.TIM_OCIdleState=TIM_OCIdleState_Set;TIM_OCInitStructure.TIM_OCNIdleState=TIM_OCNIdleState_Reset;TIM_OC1Init(TIM4,&TIM_OCInitStructure); /PWM_L初始化TIM_OC1PreloadConfig(TIM4,TIM_OCPreload_Disable); /改变点空比后,立即产生效应TIM_OCInitStructure.TIM_Pulse=PWM_R; /左轮PWM的占空比TIM_OC2Init(TIM4,&TIM_OCInitStructure); /PWM_R初始化TIM_OC2PreloadConfig(TIM4,TIM_OCPreload_Disable); /改变点空比后,立即产生效应/使能定时器4TIM_Cmd(TIM4,ENABLE);TIM_CtrlPWMOutputs(TIM4,ENABLE);程序第三步：在SysTick中断中，读取两个轮子的速（具体的方法是：每0.1秒读一次，并以此人作为速度的依据），并比较，如果以右轮为基准，则调整左轮的PWM占空比。涉及到关键语句是：TIM_SetCompare1（；）u16 COUN1=0;u16 COUN2=0;volatile u16 Dist_L=0; /左轮行程脉冲数volatile u16 Dist_R=0; /右轮行程脉冲数void SysTick_Handler(void)COUN1=TIM1-CNT; /左轮在0.1秒里脉冲数COUN2=TIM2-CNT; /右轮在0.1秒里脉冲数Dist_L=Dist_L+COUN1; /左轮行程脉冲数Dist_R=Dist_R+COUN2; /右轮行程脉冲数if( (COUN1-COUN2)2) PWM_L= TIM_GetCapture1(TIM4); TIM_SetCompare1(TIM4, PWM_L - 4); else if ( (COUN2-COUN1)2) PWM_L= TIM_GetCapture1(TIM4); TIM_SetCompare1(TIM4, PWM_L + 4); TIM_SetCounter(TIM1, 0);TIM_SetCounter(TIM2, 0);关于TIM_SetCompareX（；）这个函数，还是有很多用途的，其中另外一个用途，就是用于产生不同频率的PWM，具体程序如下：u16 capture = 0;extern vu16 CCR1_Val;extern vu16 CCR2_Val;extern vu16 CCR3_Val;extern vu16 CCR4_Val;void TIM2_IRQHandler(void)/* TIM2_CH1 toggling with frequency = 183.1 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET) TIM_ClearITPendingBit(TIM2, TIM_IT_CC1 );capture = TIM_GetCapture1(TIM2);TIM_SetCompare1(TIM2, capture + CCR1_Val );/* TIM2_CH2 toggling with frequency = 366.2 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC2) != RESET) TIM_ClearITPendingBit(TIM2, TIM_IT_CC2);capture = TIM_GetCapture2(TIM2); TIM_SetCompare2(TIM2, capture + CCR2_Val); /* TIM2_CH3 toggling with frequency = 732.4 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC3) != RESET) TIM_ClearITPendingBit(TIM2, TIM_IT_CC3);capture = TIM_GetCapture3(TIM2); TIM_SetCompare3(TIM2, capture + CCR3_Val);/* TIM2_CH4 toggling with frequency = 1464.8 Hz */if (