已經會有採樣值了.....那提供你以下的意見讓你試試...


//AD1CON2 Register
AD1CON2bits.CSCNA = 1;// Scan Input for CH0+ during Sample A bit
AD1CON2bits.VCFG= 0;
AD1CON2bits.CHPS= 0; //CH0 are used
AD1CON2bits.ALTS= 0; //Always uses channel input selects for Sample A
AD1CON2bits.SMPI= 2; //3 ADC Channel is scanned
這裡請改為2, 表示 A/D 模塊在進行3次 採樣後會將 AD1IF 設定為1。
(AD1IF 會在 SMPI + 1 的次數後被設為1, 所以 3 = (2) + 1, 設定值為2)

至於採樣的結果值,
在AD1IF = 1時, 結果值應該會依 AN0, AN1,AN2 的順序
連續儲存於 ADC1BUF0 開始的3個位置上,
即 [ADC1BUF0], [ADC1BUF0+2], [ADC1BUF0+4]這3個位置,
-----------------------------------------------------------------------
unsigned int *adc_data;
unsigned int AN0_DATA, AN1_DATA, AN2_DATA;

adc_data = &ADC1BUF0;
AN0_DATA = adc_data[0];
AN1_DATA = adc_data[1];
AN2_DATA = adc_data[2];

提取各別的採樣值大概是類似這樣吧!
-----------------------------------------------------------------------
因為是採樣3次後將AD1IF狀態設定為1,
所以.......使用中斷, 然後在中斷裡面去提取採樣值可能會蠻方便吧!

希望有高手指点一下迷津

void ADC_init()
{
//unsigned int i=0;
//AD1CON1 Register
AD1CON1bits.SSRC= 7;//Sample Clock Source :Internal counter ends sampling
//and starts conversion (auto-convert)
AD1CON1bits.FORM= 0; //Data Output Format is int
AD1CON1bits.AD12B = 1; //Select 12bit Operation Mode
AD1CON1bits.ASAM= 0; //Sampling begins when SAMP bit is set


//AD1CON2 Register
AD1CON2bits.CSCNA = 1;// Scan Input for CH0+ during Sample A bit
AD1CON2bits.VCFG= 0;
AD1CON2bits.CHPS= 0; //CH0 are used
AD1CON2bits.ALTS= 0; //Always uses channel input selects for Sample A
AD1CON2bits.SMPI= 0;//3 ADC Channel is scanned

//AD1CON3 Register
AD1CON3bits.ADRC= 0; //ADC Clock is derived from Systems Clock
AD1CON3bits.SAMC= 1; //Auto Sample Time is 1*TAD=0.4us
AD1CON3bits.ADCS= 15; // ADC Conversion Clock Tad=Tcy*(ADCS+1)=(1/40M)*16 = 0.4us>0.333us(min TAD)
// ADC Conversion Time for 12-bit Tc=14*Tad =5.6us


//AD1CHS0 Register
AD1CHS0bits.CH0NA=0; //Channel 0 negative input is VREF-

// AD1PCFG Register
//select AN0,AN1,AN2 as analog mode
AD1PCFGH= 0XFFFF ;
AD1PCFGL= 0XFFF8 ;


//AD1CSS Register
//Enable AN0,AN1,AN2 for channel scan
AD1CSSH= 0X0000;
AD1CSSL= 0X0007;


//Clear the A/D interrupt flag bit
IFS0bits.AD1IF = 0;

//clear the A/D interrupt enable bit
IEC0bits.AD1IE = 0;

AD1CON1bits.ADON = 1; //Turn on the A/D converter

}
以上是我的A/D初始化程序
我选择了12位的A/D转换器
选择AN0,AN1,AN2三个模拟端口
具体工作是对这三个端口不停的轮流采样，
且保存到各自的数组中去

但现在出现的问题是：进入采样时，没有按照AN0.AN1.AN2的顺序采
有时是先采AN2,有时又是先采AN1
这样的话我就无法正确保存每一路的数组数值