msp430f5438A，adc采样保持源选用timer

Jiejie Dai

Intellectual 263 points

Other Parts Discussed in Thread: MSP430F5438A

MCU选用MSP430F5438A，系统主频为18.432MHz，adc采样保持源选用01 Timer_A.OUT1时，单片机无法采样，代码如下：

#include "msp430x54x.h"

__no_init int Volt[1200]; //ADC转换电压 40个周期

__no_init int Crrnt[1200]; //ADC转换电流 40个周期

int Jizhun[10];

int DMAcount;

void Init_DMA()

{

DMACTL0 = DMA0TSEL_24+DMA1TSEL_24; // ADC12IFGx triggered

DMACTL1 = DMA2TSEL_24;

DMACTL4 = DMARMWDIS; // Read-modify-write disable

DMA0CTL &= ~DMAIFG;

DMA1CTL &= ~DMAIFG;

DMA2CTL &= ~DMAIFG;

DMA0CTL = DMADT_4+DMAEN+DMADSTINCR_3; // Rpt single tranfer, inc dst, int

DMA1CTL = DMADT_4+DMAEN+DMADSTINCR_3; // Rpt single tranfer, inc dst,int

DMA2CTL = DMADT_4+DMAEN+DMADSTINCR_3+DMAIE; // Rpt single tranfer, inc dst,

DMA0SZ = 1200; // DMA0 size = 12 00

DMA1SZ = 10;

DMA2SZ = 1200; // DMA2SZ = 1200;

__data16_write_addr((unsigned short) &DMA0SA,(unsigned long) &ADC12MEM13); // ... from ADC12MEM13

__data16_write_addr((unsigned short) &DMA0DA,(unsigned long) &Volt);

__data16_write_addr((unsigned short) &DMA1SA,(unsigned long) &ADC12MEM12); // ... from ADC12MEM14

__data16_write_addr((unsigned short) &DMA1DA,(unsigned long) &Jizhun);

__data16_write_addr((unsigned short) &DMA2SA,(unsigned long) &ADC12MEM15); // ... from ADC12MEM14

__data16_write_addr((unsigned short) &DMA2DA,(unsigned long) &Crrnt);

}

void main(void)

{

WDTCTL = WDTPW + WDTHOLD ; // 关看门狗

P7SEL |= 0x03;

P5SEL |= 0x0C ; // 端口功能选择振荡器

UCSCTL6 &= ~XT2OFF ;

UCSCTL3 |= SELREF_2 ;

UCSCTL4 |= SELA_0 ;

do {

UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + XT1HFOFFG + DCOFFG); // 清除 XT2,XT1,DCO 错误标志

SFRIFG1 &= ~OFIFG ;

}while(SFRIFG1&OFIFG) ; // 检测振荡器错误标志

UCSCTL6 |= XT2DRIVE0 + XT2DRIVE1 ; // XT2 驱动模式 24~32MHz

UCSCTL4 |= SELS_5 + SELM_5 ; // SMCLK = MCLK = XT2

//蓝色字体部分，系统时钟初始化，系统时钟18.432Mhz

P5SEL|=BIT0+BIT1;

P5DIR&=~(BIT0+BIT1); //ADC参考电压为外部参考电压3V

P7SEL |= BIT7+BIT4+BIT5 ; // Enable A/D channel A13,12,15

P8SEL|=BIT1;

P8DIR |= BIT1;

P6DIR|=BIT3;

_EINT();

Init_DMA();

TA0CCR0=4607;

TA0CCR1=4000;

TA0CCTL1 = OUTMOD_3; // Toggle on EQU1 (TAR = 0)

TA0CTL = TASSEL_2 + MC_1+TACLR; // SMCLK, cont-mode

ADC12CTL0 = ADC12SHT0_2 + ADC12ON ; // Config ADC12

ADC12CTL1 = ADC12SHS_1 + ADC12CONSEQ_3 +ADC12SHP+ADC12CSTARTADD_12; // TA trig., rpt conv.+ ADC12SHP

ADC12MCTL13 = ADC12SREF_2+ ADC12INCH_13 ; // Vr+=Vref+ and Vr-=AVss

ADC12MCTL12 = ADC12SREF_2+ ADC12INCH_12 ; // Vr+=Vref+ and Vr-=AVss

ADC12MCTL15 = ADC12SREF_2+ ADC12INCH_15 +ADC12EOS ; // Vr+=Vref+ and Vr-=AVss

ADC12CTL0 |=ADC12ENC;

while(1)

{ ; }

}

//////////////////DMA中断函数

#pragma vector=DMA_VECTOR

__interrupt void DMA_ISR(void)

{

switch(__even_in_range(DMAIV,16))

{

case 0: break;

case 2: break; // DMA0IFG = DMA Channel 0

case 4: break; // DMA1IFG = DMA Channel 1

case 6:

DMAcount=0;

P6OUT^=BIT3; // DMA2IFG = DMA Channel 2

case 8: break; // DMA3IFG = DMA Channel 3

case 10: break; // DMA4IFG = DMA Channel 4

case 12: break; // DMA5IFG = DMA Channel 5

case 14: break; // DMA6IFG = DMA Channel 6

case 16: break; // DMA7IFG = DMA Channel 7

default: break;

}

MCU选用MSP430F5438A，系统主频为18.432MHz，adc采样保持源选用03 Timer_B.OUT1时，单片机正常采样，并且正确，代码如下：