EEPW论坛

问 请问我使用ADC12内部参考源2.5V，如何进行零度和满度调整。我是这样做的，把参考源选为Vref+,Vref-,把输入通道选为Vref-,但这样转换后，中断后结果始终为0.不知道是不是达到零度调整。请们指点小妹。非常感谢！！！我在作毕业设计，程序调不出来啊。那如何进行满度调整呢，输入通道没有定义Vref+,啊？？？？ 答 1: Vref+,Vref-,需要外接! 答 2: 既然想使用内部参考源就不需外接参考源了。

#include "MSP430x44x.h" // Standard Equations

#define Num_of_Results 8

static unsigned int A0results[Num_of_Results]; // These need to be global in
static unsigned int A1results[Num_of_Results]; // this example. Otherwise, the
static unsigned int A2results[Num_of_Results]; // compiler removes them because
static unsigned int A3results[Num_of_Results]; // they are not used

void main(void)
{
WDTCTL = WDTPW+WDTHOLD; // Stop watchdog timer
P6SEL = 0x0F; // Enable A/D channel inputs
ADC12CTL0 = ADC12ON+MSC+SHT0_8+REF2_5V; // Turn on ADC12, extend sampling time
// to avoid overflow of results
ADC12CTL1 = SHP+CONSEQ_3+ADC12DIV_7; // Use sampling timer, repeated sequence
ADC12MCTL0 = INCH_0; // ref+=AVcc, channel = A0
ADC12MCTL1 = INCH_1; // ref+=AVcc, channel = A1
ADC12MCTL2 = INCH_2; // ref+=AVcc, channel = A2
ADC12MCTL3 = INCH_3+EOS; // ref+=AVcc, channel = A3, end seq.
ADC12IE = 0x08; // Enable ADC12IFG.3
ADC12CTL0 |= ENC; // Enable conversions
_EINT(); // Enable interrupts
ADC12CTL0 |= ADC12SC; // Start conversion
_BIS_SR(LPM0_bits); // Enter and stay in LPM0
}

interrupt[ADC_VECTOR] void ADC12ISR (void)
{
static unsigned int index = 0;

A0results[index] = ADC12MEM0; // Move A0 results, IFG is cleared
A1results[index] = ADC12MEM1; // Move A1 results, IFG is cleared
A2results[index] = ADC12MEM2; // Move A2 results, IFG is cleared
A3results[index] = ADC12MEM3; // Move A3 results, IFG is cleared
index = (index+1)%Num_of_Results; // Increment results index, modulo
} 答 3: 大侠提供的程序，我觉得还是没进行内部参考源零度和满度调整啊，我只是想把内部参考源进行零度和满度调整，不知道该怎么办 答 4: 引用: