基于msp430g2553内部ADC10单通道详解

基于msp430g2553内部ADC10单通道详解

/采用数码管显示转换结果
#include "delay.h"
#define Num_of_Results 32
static uint results[Num_of_Results];
uchar d[11]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x00};
uchar d1[10]={0xbf,0x86,0xdb,0xcf,0xe6,0xed,0xfd,0x87,0xff,0xef};
uchar a[5]={0xdf,0xef,0xf7,0xfb,0xff};
void main()
{
// Stop watchdog timer to prevent time out reset
WDTCTL = WDTPW + WDTHOLD;
//主系统时钟切换为外部高速晶振
if (CALBC1_8MHZ == 0xFF || CALDCO_8MHZ == 0xFF)
{
while(1); // If calibration constants erased, trap CPU!!
}
// Configure Basic Clock
BCSCTL1 = CALBC1_8MHZ; // Set range
DCOCTL = CALDCO_8MHZ; // Set DCO step + modulation*/

P1SEL |= BIT1+BIT0; // p1.0为A0
P1DIR&=~(BIT1+BIT0);// p1.0为输入
P2SEL=0X00;// p2为普通io口

ADC10CTL0= ADC10ON+ADC10SHT_2+MSC+ADC10IE+SREF_2;
// ADC12ON打开ADC；
//ADC10SHT_3设置采样时间,合适即可
//MSC设置多次采样
// 中断允许，IFG置位后会进入中断服务程序
ADC10CTL1= CONSEQ_2+INCH_0;
//CONSEQ_2单通道多次转换
// INCH_0选择通道A0，可以不写，默认为A0
ADC10AE0|=0X03;
ADC10SA=0X200;
ADC10CTL0 |= ENC+ADC10SC; // 使能转换并且开始转换
ADC10CTL0&=~ADC10IFG;//清除中断标志位
_EINT();//打开中断
while(1);
}
//ADC中断服务函数，在这里用多次平均的
#pragma vector=ADC10_VECTOR
__interrupt void ADC10ISR (void)
{
uchar i;
uchar ptr[4];
P1DIR=0XFC;//p4作为输出
P2DIR=0XFF;
static uint index = 0;
results[index++] = ADC10MEM;
if(index == Num_of_Results)
{
unsigned long sum = 0,real;
index = 0;
for(i = 0; i < Num_of_Results; i++)
{
sum += results;
}
sum >>= 5; //除以32求得平均值
real=3300*sum/1023;//扩大1000倍
ptr[3] = real / 1000;
ptr[2] = (real - ptr[3]*1000)/100;
ptr[1] = (real - ptr[3]*1000 - ptr[2]*100)/10;
ptr[0] = (real - ptr[3]*1000 - ptr[2]*100 - ptr[1]*10);
for(i=0;i<4;i++)
{
P1OUT=a;
if(i==3)
P2OUT=d1[ptr];
else
P2OUT=d[ptr];
__delay_cycles(30000);
P1OUT=a[4];
P2OUT=d[10];
}
}
}