关于DAC+DMA+Timer显示正弦波的问题

bbq · 发表于 2018-3-25 09:13:52

小弟弄这个很久了，下面我是参考别人库函数版本写的寄存器版本的代码，我真的不知道哪里错了，求指教！！

#define DAC_DHR12R1 (uint32_t)&(DAC->DHR12R1) //DAC通道1输出寄存器地址

//正弦波单个周期的点数
#define POINT_NUM 32

/* 波形数据 ---------------------------------------------------------*/
const uint16_t Sine12bit[POINT_NUM] = {
2048 , 2460 , 2856 , 3218 , 3532 , 3786 , 3969 , 4072 ,
4093 , 4031 , 3887 , 3668 , 3382 , 3042 , 2661 , 2255 ,
1841 , 1435 , 1054 , 714 , 428 , 209 , 65 , 3 ,
24 , 127 , 310 , 564 , 878 , 1240 , 1636 , 2048
};

uint32_t DualSine12bit[POINT_NUM];

/*
备注：DAC的配置个人感觉是完全没有问题的
*/
static void DAC_Config(void)
{
RCC->APB2ENR |= (0x1 << 2); //开启GPIOA时钟
RCC->APB1ENR |= (0x1 << 29); //开启DAC时钟

GPIOA->CRL &= ~(0x3 << 18); //模拟模式 PA4
//GPIOA->CRL &= ~(0x3 << 22); //模拟模式 PA5

DAC->CR |= (0x1 << 0); //使能DAC通道1
DAC->CR |= (0x1 << 1); //关闭DAC通道1输出缓存
DAC->CR |= (0x1 << 2); //使能DAC通道1触发
DAC->CR &= ~(0x7 << 3); //TIM6 TRGO事件
DAC->CR &= ~(0x3 << 6); //关闭波形
DAC->CR |= (0x1 << 12); //使能DAC通道1DMA模式

// DAC->CR |= (0x1 << 16); //使能DAC通道2
// DAC->CR |= (0x1 << 17); //关闭DAC通道2输出缓存
// DAC->CR |= (0x1 << 18); //使能DAC通道2触发
// DAC->CR &= ~(0x7 << 19); //TIM6 TRGO事件
// DAC->CR &= ~(0x3 << 22); //关闭波形
// DAC->CR |= (0x1 << 28); //使能DAC通道2DMA模式
}

/*
备注：APB1的定时器为72M
*/
static void DAC_TIM_Config(void)
{
RCC->APB1ENR |= (0x1 << 4); //TIM6
TIM6->CR2 |= (0x2 << 4);
TIM6->DIER &= ~(0x1 << 0); //禁止更新中断
TIM6->PSC = 7200-1;
TIM6->ARR = 10000-1;
TIM6->CR1 |= (0x1 << 0); //使能计数器
}

static void DAC_DMA_Config(void)
{
RCC->AHBENR |= (0x1 << 1); //使能DMA2
delay_ms(5); //等待DMA时钟稳定
DMA2_Channel3->CPAR = DAC_DHR12R1;
DMA2_Channel3->CMAR = (uint32_t)&DualSine12bit;
DMA2_Channel3->CNDTR = 32;
DMA2_Channel3->CCR = 0;
DMA2_Channel3->CCR |=1<<4;    //从存储器读
DMA2_Channel3->CCR |=0<<6; //外设地址非增量模式
DMA2_Channel3->CCR |=1<<7;      //存储器增量模式
DMA2_Channel3->CCR |=1<<8;      //外设数据宽度为16位
DMA2_Channel3->CCR |=1<<10; //存储器数据宽度16位

DMA2_Channel3->CCR |=1<<12; //最高优先级
DMA2_Channel3->CCR |=1<<13; //最高优先级

DMA2_Channel3->CCR &= ~(0x1 << 14); //非存储器到存储器模式
DMA2_Channel3->CCR |=1<<5;    //循环发送模式
DMA2_Channel3->CCR |=1<<0;      //开启DMA传输
}

void DAC_Mode_Init(void)
{
uint32_t Idx = 0;

DAC_Config();
DAC_TIM_Config();

/* 填充正弦波形数据，双通道右对齐*/
  for (Idx = 0; Idx < POINT_NUM; Idx++)
  {
DualSine12bit[Idx] = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);
  }

DAC_DMA_Config();

}