请教28335里ADC启动DMA的问题.

再说一下我的问题:

我现在需要AD对AIN0A和AIN0B,AIN1A和AIN1B两组信号分别进行同步的连续采样,速率5X2MSPS分别生成2个队列,SEQ1通过DMA的CH1进行传输,SEQ2通过DMA的CH2进行传输到一个数组

ADC设置如下:

void Adc_SetA(Uint16 ADC_SHCLK, Uint16 ADC_CKPS)
{
// ADC setup for Adc_Set()
AdcRegs.ADCTRL1.bit.CPS = 0; // no core pre scale
AdcRegs.ADCTRL1.bit.ACQ_PS = ADC_SHCLK; // Simultaneous: Sample rate = 1/[(3+ACQ_PS)*ADC clock in ns]
// = 1/(5*40ns) =5MHz
// If Simultaneous mode enabled: Sample rate = 1/[(3+ACQ_PS)*ADC clock in ns]
AdcRegs.ADCTRL3.bit.ADCCLKPS = ADC_CKPS;
AdcRegs.ADCTRL3.bit.SMODE_SEL = 1; // Enable Simultaneous mode同步采样
AdcRegs.ADCTRL1.bit.SEQ_CASC = 0; // 1 Cascaded mode
AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0x0;

AdcRegs.ADCTRL1.bit.CONT_RUN = 1; // Setup continuous run
AdcRegs.ADCTRL1.bit.SEQ_OVRD = 0; // Enable Sequencer override feature
AdcRegs.ADCREFSEL.bit.REF_SEL = 2; //external reference 1.500V on ADCREFIN
AdcRegs.ADCOFFTRIM.bit.OFFSET_TRIM = 0; //offset trim value

AdcRegs.ADCTRL2.bit.INT_MOD_SEQ1 = 0; //INT_SEQ1 is set at the end of SEQ1
AdcRegs.ADCTRL2.bit.INT_MOD_SEQ2 = 0; //INT_SEQ2 is set at the end of SEQ1
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1 = 0x1; //Enable SEQ1 interrupt
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ2 = 0x1; //Enable SEQ2 interrupt

AdcRegs.ADCMAXCONV.bit.MAX_CONV1 = 7; // convert and store in 8 results registers
AdcRegs.ADCMAXCONV.bit.MAX_CONV2 = 7;

AdcRegs.ADCCHSELSEQ1.all = 0x1010; // Initialize all ADC channel selects to A0
AdcRegs.ADCCHSELSEQ2.all = 0x1010;
AdcRegs.ADCCHSELSEQ3.all = 0x1010;
AdcRegs.ADCCHSELSEQ4.all = 0x1010;
}

首先打开DMACH1和DMACH2,然后用

AdcRegs.ADCTRL2.all |= 0x2000;启动SEQ1时,ADC和DMA工作正常

AdcRegs.ADCTRL2.all |= 0x0020;启动SEQ2时,ADC和DMA工作正常

但是用

AdcRegs.ADCTRL2.all |= 0x2020;同时启动SEQ1和SEQ2时,就只有SEQ1工作了,SEQ2根本没有启动

我把下面这项设置

AdcRegs.ADCTRL1.bit.SEQ_CASC = 0; // 1 Cascaded mode

改成1后,ADC的16个ADCRESULT倒是都存了数据,但是DMACH2好像没有启动,内存数组里只有前8个采样数据.

请问如何设置能让两个队列同时工作?

以上设置的主要原因是我需要连续稳定的采样数据,采样间隔一致,中间不能丢数.