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28335ADC DMA采样正弦信号失真问题

2017-08-21 分类：C2000™ 32位实时 MCU 阅读(381)

我用TMS320F28335对一个正弦信号进行采样，频率约为1kHz，正弦信号中的直流偏置为1.65v，通过CCS6.0中的Graph工具看采集的数据波形时，发现连续多个采样信号之间的值相等，整个波形呈现锯齿状，如下图所示(两个图中的数据相同，使用bar模式看的更清楚些)，ADC和DMA模块的初始化代码如下：

void pwmset()//EPWM初始化代码
{
EPwm1Regs.TBPRD=50;//4us;
EPwm1Regs.TBCTR=0;
EPwm1Regs.TBPHS.all=0;

EPwm1Regs.TBCTL.bit.FREE_SOFT=1;
EPwm1Regs.TBCTL.bit.CLKDIV=1;//sys/12
EPwm1Regs.TBCTL.bit.HSPCLKDIV=3;
EPwm1Regs.TBCTL.bit.PRDLD=0;
EPwm1Regs.TBCTL.bit.PHSEN=0;
EPwm1Regs.TBCTL.bit.CTRMODE=0;
EPwm1Regs.ETSEL.bit.SOCAEN=1;
EPwm1Regs.ETSEL.bit.SOCASEL=2;
EPwm1Regs.ETSEL.bit.SOCBEN=0;
EPwm1Regs.ETPS.bit.SOCAPRD=1;
}

void adcset()//ADC初始化代码
{
InitAdc();
AdcRegs.ADCTRL1.bit.ACQ_PS=1;//预定标系数=1
AdcRegs.ADCTRL1.bit.CONT_RUN=0;//非连续运行
AdcRegs.ADCTRL1.bit.CPS=1;//ADC模块时钟预分频
AdcRegs.ADCTRL1.bit.SEQ_CASC=1;//SEQ级联模式

AdcRegs.ADCTRL2.bit.EPWM_SOCB_SEQ=0;//
AdcRegs.ADCTRL2.bit.RST_SEQ1=1;
AdcRegs.ADCTRL2.bit.SOC_SEQ1=0;
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1=1;
AdcRegs.ADCTRL2.bit.INT_MOD_SEQ1=0;
AdcRegs.ADCTRL2.bit.EPWM_SOCA_SEQ1=1;
AdcRegs.ADCTRL2.bit.EXT_SOC_SEQ1=0;

AdcRegs.ADCTRL3.bit.SMODE_SEL=0;
AdcRegs.ADCTRL3.bit.ADCCLKPS=3;//12.5Mh;

AdcRegs.ADCCHSELSEQ1.bit.CONV00=0;
AdcRegs.ADCCHSELSEQ1.bit.CONV01=1;
AdcRegs.ADCCHSELSEQ1.bit.CONV02=2;
AdcRegs.ADCCHSELSEQ1.bit.CONV03=3;
AdcRegs.ADCCHSELSEQ2.bit.CONV04=4;
AdcRegs.ADCCHSELSEQ2.bit.CONV05=5;

AdcRegs.ADCMAXCONV.bit.MAX_CONV2=0x5;
// AdcRegs.ADCMAXCONV.bit.MAX_CONV1=0x0;
}

void dmaset()//DMA初始化代码
{
DMAInitialize();

DMADest=&DMABuf1[0];
DMASource= &AdcMirror.ADCRESULT0;
DMACH1AddrConfig(DMADest,DMASource);
DMACH1BurstConfig(6,1,512);//设置每次Burst的字节数、源地址增量、目标地址增量
DMACH1TransferConfig(511,0,0);//设置每次传送包含多少个Burst、传送完毕发中断，源地址增量、目标地址增量
DMACH1WrapConfig(0,0,0,1);//no use wrap;

EALLOW;

// Set up MODE Register:
DmaRegs.CH1.MODE.bit.PERINTSEL = DMA_SEQ1INT; // Passed DMA channel as peripheral interrupt source
DmaRegs.CH1.MODE.bit.PERINTE = PERINT_ENABLE; // Peripheral interrupt enable
DmaRegs.CH1.MODE.bit.ONESHOT = ONESHOT_DISABLE; // Oneshot disable, tansfer won't stop between bursts
DmaRegs.CH1.MODE.bit.CONTINUOUS = CONT_ENABLE; // Continous enable, channel won't be disabled at the end of transfer
DmaRegs.CH1.MODE.bit.SYNCE = SYNC_DISABLE; // Peripheral sync enable/disable
DmaRegs.CH1.MODE.bit.SYNCSEL = SYNC_SRC; // Sync effects source or destination
DmaRegs.CH1.MODE.bit.OVRINTE = OVRFLOW_DISABLE; // Enable/disable the overflow interrupt
DmaRegs.CH1.MODE.bit.DATASIZE = SIXTEEN_BIT; // 16-bit/32-bit data size transfers
DmaRegs.CH1.MODE.bit.CHINTMODE = CHINT_END; // Generate interrupt to CPU at beginning/end of transfer
DmaRegs.CH1.MODE.bit.CHINTE = CHINT_ENABLE; // Channel Interrupt to CPU enable(PIE)

// Clear any spurious flags:
DmaRegs.CH1.CONTROL.bit.PERINTCLR = 1; // Clear any spurious interrupt flags
DmaRegs.CH1.CONTROL.bit.SYNCCLR = 1; // Clear any spurious sync flags
DmaRegs.CH1.CONTROL.bit.ERRCLR = 1; // Clear any spurious sync error flags

// Initialize PIE vector for CPU interrupt:
// Enable DMA CH1 interrupt in PIE

EDIS;
}

Emma Wang：

您好

把这句话

DMACH1BurstConfig(6,1,512);//设置每次Burst的字节数、源地址增量、目标地址增量

改为

DMACH1BurstConfig(6,0,0);

我的理解，如果您只对一路转换结果进行DMA传送的话，一次源地址和目标地址增量1即可。

我用TMS320F28335对一个正弦信号进行采样，频率约为1kHz，正弦信号中的直流偏置为1.65v，通过CCS6.0中的Graph工具看采集的数据波形时，发现连续多个采样信号之间的值相等，整个波形呈现锯齿状，如下图所示(两个图中的数据相同，使用bar模式看的更清楚些)，ADC和DMA模块的初始化代码如下：

void pwmset()//EPWM初始化代码
{
EPwm1Regs.TBPRD=50;//4us;
EPwm1Regs.TBCTR=0;
EPwm1Regs.TBPHS.all=0;

EPwm1Regs.TBCTL.bit.FREE_SOFT=1;
EPwm1Regs.TBCTL.bit.CLKDIV=1;//sys/12
EPwm1Regs.TBCTL.bit.HSPCLKDIV=3;
EPwm1Regs.TBCTL.bit.PRDLD=0;
EPwm1Regs.TBCTL.bit.PHSEN=0;
EPwm1Regs.TBCTL.bit.CTRMODE=0;
EPwm1Regs.ETSEL.bit.SOCAEN=1;
EPwm1Regs.ETSEL.bit.SOCASEL=2;
EPwm1Regs.ETSEL.bit.SOCBEN=0;
EPwm1Regs.ETPS.bit.SOCAPRD=1;
}

void adcset()//ADC初始化代码
{
InitAdc();
AdcRegs.ADCTRL1.bit.ACQ_PS=1;//预定标系数=1
AdcRegs.ADCTRL1.bit.CONT_RUN=0;//非连续运行
AdcRegs.ADCTRL1.bit.CPS=1;//ADC模块时钟预分频
AdcRegs.ADCTRL1.bit.SEQ_CASC=1;//SEQ级联模式

AdcRegs.ADCTRL2.bit.EPWM_SOCB_SEQ=0;//
AdcRegs.ADCTRL2.bit.RST_SEQ1=1;
AdcRegs.ADCTRL2.bit.SOC_SEQ1=0;
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1=1;
AdcRegs.ADCTRL2.bit.INT_MOD_SEQ1=0;
AdcRegs.ADCTRL2.bit.EPWM_SOCA_SEQ1=1;
AdcRegs.ADCTRL2.bit.EXT_SOC_SEQ1=0;

AdcRegs.ADCTRL3.bit.SMODE_SEL=0;
AdcRegs.ADCTRL3.bit.ADCCLKPS=3;//12.5Mh;

AdcRegs.ADCCHSELSEQ1.bit.CONV00=0;
AdcRegs.ADCCHSELSEQ1.bit.CONV01=1;
AdcRegs.ADCCHSELSEQ1.bit.CONV02=2;
AdcRegs.ADCCHSELSEQ1.bit.CONV03=3;
AdcRegs.ADCCHSELSEQ2.bit.CONV04=4;
AdcRegs.ADCCHSELSEQ2.bit.CONV05=5;

AdcRegs.ADCMAXCONV.bit.MAX_CONV2=0x5;
// AdcRegs.ADCMAXCONV.bit.MAX_CONV1=0x0;
}

void dmaset()//DMA初始化代码
{
DMAInitialize();

DMADest=&DMABuf1[0];
DMASource= &AdcMirror.ADCRESULT0;
DMACH1AddrConfig(DMADest,DMASource);
DMACH1BurstConfig(6,1,512);//设置每次Burst的字节数、源地址增量、目标地址增量
DMACH1TransferConfig(511,0,0);//设置每次传送包含多少个Burst、传送完毕发中断，源地址增量、目标地址增量
DMACH1WrapConfig(0,0,0,1);//no use wrap;

EALLOW;

// Set up MODE Register:
DmaRegs.CH1.MODE.bit.PERINTSEL = DMA_SEQ1INT; // Passed DMA channel as peripheral interrupt source
DmaRegs.CH1.MODE.bit.PERINTE = PERINT_ENABLE; // Peripheral interrupt enable
DmaRegs.CH1.MODE.bit.ONESHOT = ONESHOT_DISABLE; // Oneshot disable, tansfer won't stop between bursts
DmaRegs.CH1.MODE.bit.CONTINUOUS = CONT_ENABLE; // Continous enable, channel won't be disabled at the end of transfer
DmaRegs.CH1.MODE.bit.SYNCE = SYNC_DISABLE; // Peripheral sync enable/disable
DmaRegs.CH1.MODE.bit.SYNCSEL = SYNC_SRC; // Sync effects source or destination
DmaRegs.CH1.MODE.bit.OVRINTE = OVRFLOW_DISABLE; // Enable/disable the overflow interrupt
DmaRegs.CH1.MODE.bit.DATASIZE = SIXTEEN_BIT; // 16-bit/32-bit data size transfers
DmaRegs.CH1.MODE.bit.CHINTMODE = CHINT_END; // Generate interrupt to CPU at beginning/end of transfer
DmaRegs.CH1.MODE.bit.CHINTE = CHINT_ENABLE; // Channel Interrupt to CPU enable(PIE)

// Clear any spurious flags:
DmaRegs.CH1.CONTROL.bit.PERINTCLR = 1; // Clear any spurious interrupt flags
DmaRegs.CH1.CONTROL.bit.SYNCCLR = 1; // Clear any spurious sync flags
DmaRegs.CH1.CONTROL.bit.ERRCLR = 1; // Clear any spurious sync error flags

// Initialize PIE vector for CPU interrupt:
// Enable DMA CH1 interrupt in PIE

EDIS;
}

Chunxu Ye：

回复 Emma Wang:

您好，我开始忘记说了，我采集了6路信号，存储在

DMABuf1[3072]//512*6

中，所以那里我设置的数值是原地址每次增加1，目标地址每次增加512，还是我对burst的设置函数理解有误？

谢谢您了！

我用TMS320F28335对一个正弦信号进行采样，频率约为1kHz，正弦信号中的直流偏置为1.65v，通过CCS6.0中的Graph工具看采集的数据波形时，发现连续多个采样信号之间的值相等，整个波形呈现锯齿状，如下图所示(两个图中的数据相同，使用bar模式看的更清楚些)，ADC和DMA模块的初始化代码如下：

void pwmset()//EPWM初始化代码
{
EPwm1Regs.TBPRD=50;//4us;
EPwm1Regs.TBCTR=0;
EPwm1Regs.TBPHS.all=0;

EPwm1Regs.TBCTL.bit.FREE_SOFT=1;
EPwm1Regs.TBCTL.bit.CLKDIV=1;//sys/12
EPwm1Regs.TBCTL.bit.HSPCLKDIV=3;
EPwm1Regs.TBCTL.bit.PRDLD=0;
EPwm1Regs.TBCTL.bit.PHSEN=0;
EPwm1Regs.TBCTL.bit.CTRMODE=0;
EPwm1Regs.ETSEL.bit.SOCAEN=1;
EPwm1Regs.ETSEL.bit.SOCASEL=2;
EPwm1Regs.ETSEL.bit.SOCBEN=0;
EPwm1Regs.ETPS.bit.SOCAPRD=1;
}

void adcset()//ADC初始化代码
{
InitAdc();
AdcRegs.ADCTRL1.bit.ACQ_PS=1;//预定标系数=1
AdcRegs.ADCTRL1.bit.CONT_RUN=0;//非连续运行
AdcRegs.ADCTRL1.bit.CPS=1;//ADC模块时钟预分频
AdcRegs.ADCTRL1.bit.SEQ_CASC=1;//SEQ级联模式

AdcRegs.ADCTRL2.bit.EPWM_SOCB_SEQ=0;//
AdcRegs.ADCTRL2.bit.RST_SEQ1=1;
AdcRegs.ADCTRL2.bit.SOC_SEQ1=0;
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1=1;
AdcRegs.ADCTRL2.bit.INT_MOD_SEQ1=0;
AdcRegs.ADCTRL2.bit.EPWM_SOCA_SEQ1=1;
AdcRegs.ADCTRL2.bit.EXT_SOC_SEQ1=0;

AdcRegs.ADCTRL3.bit.SMODE_SEL=0;
AdcRegs.ADCTRL3.bit.ADCCLKPS=3;//12.5Mh;

AdcRegs.ADCCHSELSEQ1.bit.CONV00=0;
AdcRegs.ADCCHSELSEQ1.bit.CONV01=1;
AdcRegs.ADCCHSELSEQ1.bit.CONV02=2;
AdcRegs.ADCCHSELSEQ1.bit.CONV03=3;
AdcRegs.ADCCHSELSEQ2.bit.CONV04=4;
AdcRegs.ADCCHSELSEQ2.bit.CONV05=5;

AdcRegs.ADCMAXCONV.bit.MAX_CONV2=0x5;
// AdcRegs.ADCMAXCONV.bit.MAX_CONV1=0x0;
}

void dmaset()//DMA初始化代码
{
DMAInitialize();

DMADest=&DMABuf1[0];
DMASource= &AdcMirror.ADCRESULT0;
DMACH1AddrConfig(DMADest,DMASource);
DMACH1BurstConfig(6,1,512);//设置每次Burst的字节数、源地址增量、目标地址增量
DMACH1TransferConfig(511,0,0);//设置每次传送包含多少个Burst、传送完毕发中断，源地址增量、目标地址增量
DMACH1WrapConfig(0,0,0,1);//no use wrap;

EALLOW;

// Set up MODE Register:
DmaRegs.CH1.MODE.bit.PERINTSEL = DMA_SEQ1INT; // Passed DMA channel as peripheral interrupt source
DmaRegs.CH1.MODE.bit.PERINTE = PERINT_ENABLE; // Peripheral interrupt enable
DmaRegs.CH1.MODE.bit.ONESHOT = ONESHOT_DISABLE; // Oneshot disable, tansfer won't stop between bursts
DmaRegs.CH1.MODE.bit.CONTINUOUS = CONT_ENABLE; // Continous enable, channel won't be disabled at the end of transfer
DmaRegs.CH1.MODE.bit.SYNCE = SYNC_DISABLE; // Peripheral sync enable/disable
DmaRegs.CH1.MODE.bit.SYNCSEL = SYNC_SRC; // Sync effects source or destination
DmaRegs.CH1.MODE.bit.OVRINTE = OVRFLOW_DISABLE; // Enable/disable the overflow interrupt
DmaRegs.CH1.MODE.bit.DATASIZE = SIXTEEN_BIT; // 16-bit/32-bit data size transfers
DmaRegs.CH1.MODE.bit.CHINTMODE = CHINT_END; // Generate interrupt to CPU at beginning/end of transfer
DmaRegs.CH1.MODE.bit.CHINTE = CHINT_ENABLE; // Channel Interrupt to CPU enable(PIE)

// Clear any spurious flags:
DmaRegs.CH1.CONTROL.bit.PERINTCLR = 1; // Clear any spurious interrupt flags
DmaRegs.CH1.CONTROL.bit.SYNCCLR = 1; // Clear any spurious sync flags
DmaRegs.CH1.CONTROL.bit.ERRCLR = 1; // Clear any spurious sync error flags

// Initialize PIE vector for CPU interrupt:
// Enable DMA CH1 interrupt in PIE

EDIS;
}

Chunxu Ye：

回复 Emma Wang:

您说的方法我已经试过了，但锯齿情况依然没有消除，我仔细观察了一下锯齿，发现不论信号频率、幅度为多少，锯齿的每组均为16个相同的值，我怀疑是ADC和DMA配合的问题，我已经在另外一个帖子中贴出了我的全部代码，其他未贴出的代码基本为官方的头文件。

代码链接：http://www.deyisupport.com/question_answer/microcontrollers/c2000/f/56/t/138546.aspx

这个帖子我先结贴了，谢谢您的帮助！！！

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