本帖最后由 cr315 于 2020-12-2 10:34 编辑
单片机型号MSP430FR6972我想用ADC序列通道采样，通道0-1，触发DMA，把ADC采样的数据存到flash里去。单片机打断点的情况下，定时器每次触发ADC采样后，flash里更新了一个采样值，但是，实际情况是，采样完1s的数据，我看内存中的数据，两两是相同的，如下图，
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给我的感觉像两个ADC12IFGx标志触发了采样，但是pdf也写了，有最后的ADC12IFGx触发DMA，
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不知道是不是还需要别的设置。
做过的测试：
1.保留DMA0，注释DMA1，0-1通道序列采，值还是两两重复的。
2.保留DMA0，注释DMA1，0通道序列采样，值是正常的。
3.保留DMA0，注释DMA1，0-1通道单次序列采，flash里更新了两个值，的确触发了两次。
ADC和DMA配置如下：
- void startADC(void)
- {
- while(REFCTL0 & REFGENBUSY); // If ref generator busy, WAIT
- REFCTL0 |= REFVSEL_2 | REFON; // Select internal ref = 2.5V
- // Internal Reference ON
- // Configure ADC12
- ADC12CTL0 = ADC12ON | ADC12SHT0_2; // Turn on ADC12, set sampling time 16 ADC12CLK
- ADC12CTL1 = ADC12SHP |ADC12SHS_1 | ADC12CONSEQ_3 ; // Timer_A TA0 CCR1触发采样，序列通道采样 0-1
- ADC12CTL3 = ADC12CSTARTADD_0;
- ADC12MCTL0 = ADC12INCH_2 | ADC12VRSEL_1 ;
- ADC12MCTL1 = ADC12INCH_3 | ADC12VRSEL_1 | ADC12EOS;
- //ADC12IER0 = ADC12IE1;
- ADC12CTL0 |= ADC12ENC | ADC12SC;
- // Configure DMA channel 0
- __data16_write_addr((unsigned short) &DMA0SA,(unsigned long) &ADC12MEM0);// Source block address
- __data16_write_addr((unsigned short) &DMA0DA,(unsigned long) 0x10000);// Destination address 0x10000
- DMA0SZ = 4000; // Block size
- DMACTL0 |= DMA0TSEL_26; //触发源选择ADC12采样完成
- DMA0CTL = DMADT_4 | DMASRCINCR_0 | DMADSTINCR_3; // Rpt, inc
- DMA0CTL |= DMAEN; // Enable DMA0
- // Configure DMA channel 1
- __data16_write_addr((unsigned short) &DMA1SA,(unsigned long) &ADC12MEM1);// Source block address
- __data16_write_addr((unsigned short) &DMA1DA,(unsigned long) 0x12000);// Destination address 0x12000
- DMA1SZ = 4000; // Block size
- DMACTL0 |= DMA1TSEL_26; //触发源选择ADC12采样完成
- DMA1CTL = DMADT_4 | DMASRCINCR_0 | DMADSTINCR_3; // Rpt, inc
- //DMA1CTL |= DMAEN; // Enable DMA1
- }
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