用adc采样的波形周期性混乱

bugerror

用da生成一组锯齿波在用ad采集。示波器上看还是好好的，把ad采到的数据放到matlab看就发现有周期性的混乱。均使用dma传输，中断同步。附上ad和da的代码，

1. #include "sys.h"
   
2. #include "math.h"
   
3. #include "dac.h"
   
4. #include "delay.h"
   
5. #include "led.h"
   
6. #define DAC_DHR12R1_ADDRESS 0x40007408
   
7. 
   
8. u16 sawtooth[tableSize];// tableSize==250
   
9. u16 led1=0;
   
10. 
    
11. //锯齿波
    
12. void sawtooth_Generation(void)
    
13. {
    
14.         u16 n;
    
15.         for(n=0;n<tableSize;n++)
    
16.         {
    
17.                 sawtooth[n] = n*16;
    
18.         }
    
19. }
    
20. 
    
21. void TIM6_Configuration(void)
    
22. {
    
23.         RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM6, ENABLE);
    
24. 
    
25.         TIM_PrescalerConfig(TIM6, 83, TIM_PSCReloadMode_Update); //设置分频系数为83
    
26.   TIM_SetAutoreload(TIM6, 3); //设置自动重载寄存器值为3
    
27.         TIM_SelectOutputTrigger(TIM6, TIM_TRGOSource_Update);
    
28.         TIM_Cmd(TIM6, ENABLE);
    
29. }
    
30. 
    
31. void DacGPIO_Configuration(void)
    
32. {
    
33.         GPIO_InitTypeDef GPIO_InitStructure;//结构体
    
34.   RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);//使能GPIOA时钟
    
35.         GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;//选定PA4
    
36.         GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;//模拟输入
    
37.         GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    
38.         GPIO_Init(GPIOA, &GPIO_InitStructure);//GPIOA初始化
    
39. }
    
40. 
    
41. void DAC_DMA_Configuration(void)
    
42. {
    
43.         DAC_InitTypeDef  DAC_InitStructure;        //DAC结构体
    
44.         DMA_InitTypeDef DMA_InitStructure; //DMA结构体
    
45.         NVIC_InitTypeDef NVIC_InitStructure;
    
46. 
    
47.         RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);
    
48.         RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);//使能DAC时钟
    
49. 
    
50.         DAC_InitStructure.DAC_Trigger = DAC_Trigger_T6_TRGO;//使用触发功能
    
51.         DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;//不用STM32自带的波形
    
52.         DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;//设置不使用输出缓存
    
53.         DAC_Init(DAC_Channel_1, &DAC_InitStructure);
    
54.         //DMA1请求映射，DMA的数据流5和通道7为DAC1功能
    
55.         DMA_DeInit(DMA1_Stream5);//设置数据流5
    
56.         DMA_InitStructure.DMA_Channel = DMA_Channel_7;//设置通道7  
    
57.         DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR12R1_ADDRESS;
    
58.         DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&sawtooth;//定义DMA外设基地址
    
59.         DMA_InitStructure.DMA_BufferSize = tableSize; //设置DMA缓存大小
    
60.         //外设数据宽度
    
61.         DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
    
62.         DMA_InitStructure.DMA_MemoryDataSize = DMA_PeripheralDataSize_HalfWord;
    
63.         DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
    
64.         DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    
65.         DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    
66. 
    
67.         DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; //设置为正常模式
    
68.         DMA_InitStructure.DMA_Priority = DMA_Priority_High;
    
69.         DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
    
70.         DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
    
71.         DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    
72.         DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    
73.         DMA_Init(DMA1_Stream5, &DMA_InitStructure);
    
74.         DMA_Cmd(DMA1_Stream5, ENABLE); //使能DMA1数据流5
    
75.         DAC_Cmd(DAC_Channel_1, ENABLE); //使能DAC的通道1
    
76.         //链接DAC通道和DMA通道
    
77.         DAC_DMACmd(DAC_Channel_1, ENABLE);//使能DAC_DMA通道1
    
78. 
    
79.         DMA_ITConfig(DMA1_Stream5,DMA_IT_TC,ENABLE);//开启传输完成中断
    
80.         NVIC_InitStructure.NVIC_IRQChannel = DMA1_Stream5_IRQn;
    
81.         NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0X00;
    
82.         NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0X00;
    
83.         NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    
84.         NVIC_Init(&NVIC_InitStructure);
    
85. }
    
86. 
    
87. void DMA1_Stream5_IRQHandler(void)
    
88. {
    
89.         if(DMA_GetFlagStatus(DMA1_Stream5,DMA_FLAG_TCIF5)==SET) //传输完成标志
    
90.                 {
    
91.                         led1++;
    
92.                         if(led1==100)
    
93.                         {
    
94.                                 LED1=!LED1;
    
95.                                 led1=0;
    
96.                         }
    
97.                         ADC_SoftwareStartConv(ADC1); //启动一次ADC
    
98.                         DMA_ClearFlag(DMA1_Stream5,DMA_FLAG_TCIF5); //清除传输完成中断
    
99.     }
    
100. }
     
101. 
     
102. void MYDAC_Init(void)
     
103. {
     
104.         sawtooth_Generation();
     
105.         DacGPIO_Configuration();
     
106.         TIM6_Configuration();
     
107.         DAC_DMA_Configuration();
     
108. }
     
109. 
     
110. 
     
111. 
     
112. #include "adc.h"
     
113. #include "delay.h"
     
114. #include "usart.h"
     
115. #include "led.h"
     
116. #define len 1400
     
117. 
     
118. u16 ADC_ConvertedValue[len];
     
119. u16 save[len];
     
120. u16 counter;
     
121. u16 led=0;
     
122. 
     
123. void ADC_DMA_Config(void)
     
124. {
     
125.         ADC_InitTypeDef ADC_InitStructure;
     
126.         ADC_CommonInitTypeDef ADC_CommonInitStructure;
     
127.         DMA_InitTypeDef DMA_InitStructure;
     
128.         GPIO_InitTypeDef GPIO_InitStructure;
     
129.         NVIC_InitTypeDef NVIC_InitStructure;
     
130. 
     
131.         RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2 | RCC_AHB1Periph_GPIOA , ENABLE);
     
132.         RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
     
133.        
     
134.         GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
     
135.         GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
     
136.         GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
     
137.         GPIO_Init(GPIOA, &GPIO_InitStructure);
     
138. 
     
139.         ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent; //独立模式
     
140.         ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div4; //4分频
     
141.         ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_1;
     
142.         ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles; //两次采样间隔5周期
     
143.         ADC_CommonInit(&ADC_CommonInitStructure);
     
144. 
     
145.         ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b; //12位模式
     
146.         ADC_InitStructure.ADC_ScanConvMode = DISABLE; //关闭扫描模式
     
147.         ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; //单次转换
     
148.         ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None; //软件触发
     
149.         ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //右对齐
     
150.         ADC_InitStructure.ADC_NbrOfConversion = 1;
     
151.         ADC_Init(ADC1, &ADC_InitStructure);
     
152. 
     
153.         ADC_RegularChannelConfig(ADC1, ADC_Channel_5, 1, ADC_SampleTime_3Cycles); //采样3周期
     
154.         ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);
     
155.         ADC_DMACmd(ADC1, ENABLE);
     
156.         ADC_Cmd(ADC1, ENABLE);
     
157. 
     
158.         DMA_DeInit(DMA2_Stream0);
     
159.         DMA_InitStructure.DMA_Channel = DMA_Channel_0; //选择通道0
     
160.         DMA_InitStructure.DMA_PeripheralBaseAddr = ((u32)ADC1+0x4c); //外设基地址
     
161.         DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&ADC_ConvertedValue; //数据存放地址
     
162.         DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory; //设置外设到内存
     
163.         DMA_InitStructure.DMA_BufferSize = len; //设置一次传输数据大小
     
164.         DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //外设地址不变
     
165.         DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //内存地址递增
     
166.         DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
     
167.         DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
     
168.         DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; //设置为循环模式
     
169.         DMA_InitStructure.DMA_Priority = DMA_Priority_Medium; //中等优先级
     
170.         DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
     
171.         DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
     
172.         DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
     
173.         DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
     
174.         DMA_Init(DMA2_Stream0, &DMA_InitStructure); //初始化
     
175.         DMA_Cmd(DMA2_Stream0, ENABLE);
     
176. 
     
177.         DMA_ITConfig(DMA2_Stream0,DMA_IT_TC,ENABLE); //开启传输完成中断
     
178.         NVIC_InitStructure.NVIC_IRQChannel = DMA2_Stream0_IRQn;
     
179.         NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0X00;
     
180.         NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0X01;
     
181.         NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
     
182.         NVIC_Init(&NVIC_InitStructure);
     
183. }
     
184. 
     
185. void DMA2_Stream0_IRQHandler(void)
     
186. {
     
187.         if(DMA_GetFlagStatus(DMA2_Stream0,DMA_FLAG_TCIF0)==SET) //传输完成标志
     
188.                 {
     
189.                         led++;
     
190.                         if(led==100)
     
191.                         {
     
192.                                 LED0=!LED0;
     
193.                                 led=0;
     
194.                         }
     
195.                         for(counter=0;counter<len;counter++)
     
196.                         save[counter]=ADC_ConvertedValue[counter];
     
197.                         DMA_ClearFlag(DMA2_Stream0,DMA_FLAG_TCIF0); //清除传输完成中断
     
198.     }
     
199. }
     

复制代码

板子是探索者f407。

bugerror

发现开启输出缓冲就好了

bugerror

照片倒了大家将就一下吧

HXYDJ

采样值滤波后在用，直接采样的值会出现抖动。