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基础实验-PWM电机驱动实验

PWM是电机驱动的基础，也是控制的基础。简单来说就是改变占空比来改变方波的等效电压，所以占空比越大，等效电压越大，电机也就转的越快。

下面给出配置代码

/************************************************************************\
*	函数名：TIM2_Initialization
*	函数功能概述：PWM初始化
*	参数说明：
*	返回值说明：
\************************************************************************/
void TIM2_Initialization(void)
{
	GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	TIM_OCInitTypeDef  TIM_OCInitStructure;
	
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
	
	//PA0-1-2-3:PWM
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	
	/* Time base configuration */
  TIM_TimeBaseStructure.TIM_Period = 100;
  TIM_TimeBaseStructure.TIM_Prescaler = (uint16_t)((36000000 / 1000000) - 1);//1MHz
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
	TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
	
	/* PWM1 Mode configuration: Channel1 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = 0;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

  TIM_OC1Init(TIM2, &TIM_OCInitStructure);

  TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);
	/* PWM1 Mode configuration: Channel2 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = 0;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

  TIM_OC2Init(TIM2, &TIM_OCInitStructure);

  TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable);
	/* PWM1 Mode configuration: Channel3 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = 0;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

  TIM_OC3Init(TIM2, &TIM_OCInitStructure);

  TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Enable);
	/* PWM1 Mode configuration: Channel4 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = 0;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

  TIM_OC4Init(TIM2, &TIM_OCInitStructure);

  TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable);
	
	TIM_ARRPreloadConfig(TIM2, ENABLE);
	
	TIM_Cmd(TIM2, ENABLE);
}

PWM是通过定时器模块产生的，首先配置定时器的基础部分，分频、计数模式、溢出值等等，在配置各个通道的输出方式，初始的比较值等等，因为是上电初始化，所以TIM_Pulse = 0;

通过TIM_SetCompare1等函数就可以改变通道的比较值，也就改变了PWM的占空比。

int main(void)
{
	int32_t i;
	Hardware_Initialization();
	
	USART1_SendStr(" QuadCopter DIY\r\n");
	
	while(1)
	{
		LED_Dx_ON();
		LED_D1_OFF();
		Wait_for(100);
		LED_Dx_OFF();
		LED_D1_ON();
		Wait_for(100);
		USART1_SendNum(i++);USART1_SendStr("\r\n");
		TIM_SetCompare1(TIM2, i % 30);
		TIM_SetCompare2(TIM2, i % 30);
		TIM_SetCompare3(TIM2, i % 30);
		TIM_SetCompare4(TIM2, i % 30);
	}
}

MPU6050的官方网站地址

http://www.invensense.com/mems/gyro/mpu6050.html

可以在上面下载数据手册还有寄存器地址（竟然还把两个分开，最开始下载数据手册里没有找到寄存器说明还很纳闷呢）