新手提问：STM32用DAC和DMA输出正弦波问题

铁板上的牛排 · 发表于 2016-6-13 11:20:19

本帖最后由铁板上的牛排于 2016-6-13 11:44 编辑

不知干嘛，输出没反应，不知道哪里没调好，小白，第一次写DAC和DMA，DAC是没问题，但DMA使用不了，看了好久都不知道哪里错了，麻烦大神帮我看看哪里错了？谢谢

DMA程序：

#include "stm32f10x.h"
#include "dac.h"
#include "dma.h"
#include "delay.h"
#include "sys.h"
#include "usart.h"

uc8 sine_tab[100]={
0x7F,0x87,0x8F,0x97,0x9F,0xA6,0xAE,0xB5,0xBC,0xC3,0xCA,0xD0,0xD6,0xDC,0xE1,0xE6
,0xEB,0xEF,0xF2,0xF6,0xF8,0xFA,0xFC,0xFD,0xFE,0xFE,0xFE,0xFD,0xFC,0xFA,0xF8,0xF6
,0xF2,0xEF,0xEB,0xE6,0xE1,0xDC,0xD6,0xD0,0xCA,0xC3,0xBC,0xB5,0xAE,0xA6,0x9F,0x97
,0x8F,0x87,0x7F,0x77,0x6F,0x67,0x5F,0x58,0x50,0x49,0x42,0x3B,0x34,0x2E,0x28,0x22
,0x1D,0x18,0x13,0x0F,0x0C,0x08,0x06,0x04,0x02,0x01,0x00,0x00,0x00,0x01,0x02,0x04
,0x06,0x08,0x0C,0x0F,0x13,0x18,0x1D,0x22,0x28,0x2E,0x34,0x3B,0x42,0x49,0x50,0x58
,0x5F,0x67,0x6F,0x77
};

void MYDMA_Config(DMA_Channel_TypeDef* DMA_CHx,u32 cpar,u32 cmar,u16 cndtr)
{
   RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); //使能DMA传输

DMA_DeInit(DMA_CHx); //将DMA的通道1寄存器重设为缺省值
DMA1_MEM_LEN=cndtr;
DMA_InitStructure.DMA_PeripheralBaseAddr = cpar;  //DMA外设ADC基地址
DMA_InitStructure.DMA_MemoryBaseAddr = cmar;  //DMA内存基地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;  //数据传输方向，从内存读取发送到外设
DMA_InitStructure.DMA_BufferSize = cndtr;  //DMA通道的DMA缓存的大小
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;  //外设地址寄存器不变
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;  //内存地址寄存器递增
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;  //数据宽度为8位
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; //数据宽度为8位
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;  //工作在正常缓存模式
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium; //DMA通道 x拥有中优先级
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;  //DMA通道x没有设置为内存到内存传输
DMA_Init(DMA_CHx, &DMA_InitStructure);  //根据DMA_InitStruct中指定的参数初始化DMA的通道USART1_Tx_DMA_Channel所标识的寄存器

}
//开启一次DMA传输
void MYDMA_Enable(DMA_Channel_TypeDef*DMA_CHx)
{
DMA_Cmd(DMA_CHx, DISABLE );  //关闭USART1 TX DMA1 所指示的通道
   DMA_SetCurrDataCounter(DMA1_Channel4,DMA1_MEM_LEN);//DMA通道的DMA缓存的大小
   DMA_Cmd(DMA_CHx, ENABLE);  //使能USART1 TX DMA1 所指示的通道
}

int main(void)
{
   u8 aa;
      Dac1_Init();          //DAC通道1初始化

      MYDMA_Config(DMA1_Channel4,(u32)&DAC->DHR8R1,(u32)sine_tab,50);

      DAC_DMACmd(DAC_Channel_1,ENABLE);

   MYDMA_Enable(DMA1_Channel4);


      while(1)
      {
      MYDMA_Enable(DMA1_Channel4);
      }
}

这样设置无输出，不知这样设置对吗？