本帖最后由 shijizai 于 2018-7-25 17:31 编辑

stm32F4想用TIM+DMA+DAC转换，大神帮忙看看程序差哪，示波器显示不出波形
这个是主函数

#include "dac.h"
#include "sys.h"
#include "delay.h"
#include "led.h"
u16 Sine12bit[32] = {
2047, 2447, 2831, 3185, 3498, 3750, 3939, 4056, 4095, 4056,
3939, 3750, 3495, 3185, 2831, 2447, 2047, 1647, 1263, 909,
599, 344, 155, 38, 0, 38, 155, 344, 599, 909, 1263, 1647  };

int main(void)
{
   
  GPIO_InitTypeDef GPIO_InitStructure;

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);                        
   
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  TIM6_Config(5000-1,840-1);  
    delay_init(168);
  while (1)
  {   
        DAC_DeInit();
        DAC_Ch2_SineWaveConfig();

//        DAC_SetChannel2Data(DAC_Align_12b_R, 100);
//        DAC_SetChannel2Data(DAC_Align_12b_R, 3000);
  }
}
这个是DAC+TIM+DMA的函数
#include "dac.h"
#include "sys.h"
#include "led.h"
extern u16 Sine12bit[32];

void TIM6_Config(u16 arr, u16 psc)
{
  TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM6, ENABLE);

  TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
  TIM_TimeBaseStructure.TIM_Period = arr;         
  TIM_TimeBaseStructure.TIM_Prescaler = psc;      
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;   
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  
  TIM_TimeBaseInit(TIM6, &TIM_TimeBaseStructure);

  TIM_SelectOutputTrigger(TIM6, TIM_TRGOSource_Update);

  TIM_Cmd(TIM6, ENABLE);

}

void DAC_Ch2_SineWaveConfig(void)
{
    DMA_InitTypeDef DMA_InitStructure;
    DAC_InitTypeDef  DAC_InitStructure;
   
  DMA_DeInit(DMA1_Stream6);
  DMA_InitStructure.DMA_Channel = DMA_Channel_7;  
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&DAC->DHR12R2;
  DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&Sine12bit;
  DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
  DMA_InitStructure.DMA_BufferSize = 32;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         
  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
  DMA_Init(DMA1_Stream6, &DMA_InitStructure);
   
    DMA_Cmd(DMA1_Stream6, ENABLE);

  DAC_InitStructure.DAC_Trigger = DAC_Trigger_T6_TRGO;
//    DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;
  DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
  DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;
    DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bit0;
  DAC_Init(DAC_Channel_2, &DAC_InitStructure);

  DAC_Cmd(DAC_Channel_2, ENABLE);

  DAC_DMACmd(DAC_Channel_2, ENABLE);
   
//    DAC_SetChannel2Data(DAC_Align_12b_R,0);
   
}
这个是.h文件
#ifndef __dac_H
#define __dac_H
#include "sys.h"

void TIM6_Config(u16 arr, u16 psc);
void DAC_Ch2_SineWaveConfig(void);

#endif
期待大神。。。

此帖出自小平头技术问答