ADS1118通道混乱了

需要多通道ADC采集，发现使用单通道的时候可以正确的读出每个通道的ADC值，如果程序中采集多个通道的电压，就会发现通道错位的情况，比如通道0上的电压到通道1上，通道1上的电压值到通道2上，或者通道2的电压到通道0,2上。CPU用的是MSP430F6638，调试了一下感觉是程序的问题，请专家看一下是什么情况，谢谢！

void __DELAY(u32 n)
{
   u32 m=4*n;
   while(m–);
};

void SPIA1_Init(void)
{
    P8SEL |= BIT1+BIT2+BIT3;                      // Assign P8.1 to UCB0CLK and…
    P8DIR |= BIT0+BIT1+BIT2;                     // P8.3 UCB0SOMI P8.2 UCB0SIMO

    UCA1CTL1 |= UCSWRST;                      // **Put state machine in reset**
    UCA1CTL0 |= UCMST+UCSYNC+UCMSB;           // 3-pin, 8-bit SPI master
                                              // Clock polarity high, MSB
    UCA1CTL1 |= UCSSEL__SMCLK;                     // SMCLK
    UCA1BR0 = 106;                         
    UCA1BR1 = 0;                              //
    UCA1MCTL = 0;                             // No modulation
    UCA1CTL1 &= ~UCSWRST;                     // **Initialize USCI state machine**
 //       UCA1IE = UCRXIE+ UCTXIE;                         // Enable USCI_A0 RX,TX interrupt
}

/*MODE 0: Only write config regist to ADS1118
  MODE 1: Write config regist to ADS1118 as well as read data from ADS1118
*/
int ADS1118_WriteSPI(u32 config,u8 mode)
{
  u32 temp;
  temp=config;
  if(mode==1)
  temp=config|0x8000;
  int msb;

  while (!(UCA1IFG&UCTXIFG));
  UCA1TXBUF = (temp>>8);
   __DELAY(100);

  while (!(UCA1IFG&UCRXIFG));
  msb = UCA1RXBUF;
  while (!(UCA1IFG&UCTXIFG));
  UCA1TXBUF = (temp & 0xff);
  __DELAY(100);
  while (!(UCA1IFG&UCRXIFG));

  msb = (msb<<8) | UCA1RXBUF;
  return msb;
}

void ADS1118_Config(u32 congfig_value)
{
  CLR_AD_CS;                           //set CS low
  __DELAY(100);                        //Wait for slave to initialize
  ADS1118_WriteSPI(congfig_value,0);  //Write configuration to ADS1118
  __DELAY(100);
  SET_AD_CS;
}

int ADS1118_Read(u32 config_value)
{
  int DATA;
  CLR_AD_CS;
  __DELAY(100);
 // delay_ms(1);
  DATA = ADS1118_WriteSPI(config_value,1);
  __DELAY(100);
  //delay_ms(1);
  SET_AD_CS;
  return DATA;
}

int ADS1118(u32 congfig_value)
{
  int result;
  SET_AD_CS;
  ADS1118_Config(congfig_value);
  __DELAY(1000);
 // delay_ms(5);
  result = ADS1118_Read(congfig_value);
  return result;
}

int GetADC_0(void)
{
    return ADS1118(0x458B);
    //return ADS1118(0xC58B);
}

int GetADC_1(void)
{
    return ADS1118(0x558B);
    //return ADS1118(0xD58B);
}

int GetADC_2(void)
{
    return ADS1118(0x658B);
    //return ADS1118(0xE58B);
}

int GetADC_3(void)
{
    return ADS1118(0x758B);
    //return ADS1118(0xF58B);
}

Jason Shen：

程序的问题建议转到MSP430的论坛会比较好一些。如果单个通道能采样，而且单个通道采样模型下可以切换到任意一个通道，那么做多通道采样就应该没啥问题。

xin wang23：

回复 Jason Shen:

现在的的现象，像是每次得到的数据都是上一次本应该读出来的数据。MSP430论坛有推荐的吗？