一个简单的光强度检测程序

1万 · 2013-9-8 16:37

BH1750FVI是光强度传感器，支持IIC接口。小弟最近欲做一个简单的光强度检测程序，将光强度用数码管显示出来，不过调试了好久一直无法工作。请各位大虾帮忙看下IIC的模拟哪里有错，不胜感激！

1万 · 2013-9-8 16:37

#include<msp430x14x.h>
#define uchar unsigned char
#define uint unsigned int
#define SDA_1  P3OUT|=BIT1 // P3.1为SDA
#define SDA_0  P3OUT&=~BIT1
#define SCL_1 P3OUT |= BIT0 //P3.0为SCL
#define SCL_0 P3OUT &= ~BIT0
#define DIR_IN P3DIR &= ~BIT1
#define DIR_OUT P3DIR |= BIT1
#define SDA_IN ((P3IN >> 1) & 0x01)
#define dis_data  P5OUT  //数码管输出
#define TIME 5
#define SlaveAddress 0xA6

uchar seg_bcd[] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e}; //数码管

void delay_nms(unsigned int k)//延时k毫秒
{
unsigned int i,j;
for(i=0;i<k;i++)
   {
   for(j=0;j<121;j++)
      {;}
   }
}
void Delay(unsigned int n) //延时
{
unsigned int i;
for(i = 0;i < n;i++)
   {
   ;
   }
}

void BH1750_Start()       //起始信号
{
   DIR_OUT;
   SDA_1;
delay_nms(5);
   SCL_1;
   Delay(TIME);
   SDA_0;
   Delay(TIME);
   SCL_0;
}

void BH1750_Stop()       //结束信号
{
   DIR_OUT;
   SDA_0;
   Delay(TIME);
   SCL_1;
   Delay(TIME);
   SDA_1;                   }

void BH1750_SendACK()    //发送Ack
{
   SCL_0;
   DIR_OUT;
   SDA_0;
   Delay(TIME);
   SCL_1;
   Delay(TIME);
   SCL_0;
}

void BH1750_RecvACK()       //接受ACK
{ SCL_1;
Delay(TIME);
   DIR_IN;
   while(SDA_IN);
   DIR_OUT;
   SCL_0;
   Delay(TIME);
}

void BH1750_SendByte(uchar dat)    //发送一个字节
{ DIR_OUT;
   unsigned int i;
   for(i = 0;i < 8;i++)
   {
   SCL_0;
   Delay(TIME);
   if((dat >> 7) & 0x01) SDA_1;
   else SDA_0;
Delay(TIME);
   SCL_1;
   Delay(TIME);
   dat <<= 1; //数据左移一位,进入下一轮送数
   }
   Delay(TIME);
}

uchar BH1750_RecvByte()       //接受一个字节
{
   uchar i;
   uchar dat = 0;
   uchar datbit=0;
   SCL_0;
   Delay(TIME);
   SDA_1;
   DIR_IN;
   for (i=0; i<8; i++)
   {
      SCL_1;
      Delay(TIME);
      datbit = SDA_IN;
      Delay(TIME);
      dat = ((dat << 1) | datbit);
      SCL_0;
      Delay(TIME);
}
   return dat;
}

void Single_Write_BH1750(uchar REG_Address)  //写入
{
   BH1750_Start();
   BH1750_SendByte(SlaveAddress);
   BH1750_SendByte(REG_Address);
// BH1750_SendByte(REG_data);
   BH1750_Stop();
}

void main()
{ uchar tmp;
float temp;
int t;
WDTCTL = WDTPW + WDTHOLD;
P5DIR |= 0Xff;
P4DIR |= 0x01;
P5OUT |= 0x00;
delay_nms(200);
Single_Write_BH1750(0x01);
Single_Write_BH1750(0x10);
  while(1)
{ Single_Write_BH1750(0x01);
   Single_Write_BH1750(0x10);
   delay_nms(180);
   tmp=BH1750_RecvByte();
   temp=(float)tmp;
   t=temp/100;
   dis_data=seg_bcd[t];
}
}