tlc2543.c

714771878051_MODBUS_RTU.rar

/*
[文件名] TLC2543.c
[作者] 鞠春阳
[版本] 1.0
*/

#include "reg51.h"
#include "intrins.h"
sbit CLK   = P1^0;
sbit DIN   = P1^1;
sbit DOUT  = P1^2;
sbit CS    = P1^3;

/*2543通道的选择，与设置*/
unsigned int TLC2543(unsigned char port)         //从TLC2543读取采样值,形参port是采样的通道号
    {
    unsigned int  value;                             //转换结果
    unsigned char i;                                 //计数器
    unsigned char lowbyte=0,highbyte=0;              //初始化为0
    CLK=0;
    CS=0;
    port<<=4;
    for (i=0;i<4;i++)                                //把通道号打入2543
        { 
        DIN=(bit)(port&0x80);
        CLK=1;
        CLK=0;
        port<<=1;
        }
    DIN=0;                   //??
          //fast mode 1
    for (i=0;i<8;i++)                               //填充6个CLOCK
        {    
		CLK=1;
        CLK=0;
        }
    CS=1;
    delay();
    CS=0;                                           //等待AD转换
    for (i=0;i<4;i++)                               //取D11,D10,D9,D8, 送到highbyte
        {
        DOUT=1;
        CLK=1;
        highbyte<<=1;
        if(DOUT) highbyte=highbyte|0x01;  //??
        CLK=0;
        }
    for (i=0;i<8;i++)                               //取D7--D0,送到lowbyte
        {
        DOUT=1;
        CLK=1;
        lowbyte<<=1;
        if(DOUT) lowbyte=lowbyte|0x01;    //??
        CLK=0;
        }
    CS=1;
    value=(unsigned int)highbyte;
    value<<=8;
    value=value|lowbyte;
    value=(unsigned int)value;                      //得到AD值
    return (value);                                 //返回结果
    }


/*读2543的某一个通道*/
ReadTLC2543(unsigned char x)
   {
   unsigned int i=0;
   float j=0;
   j=TLC2543(0);
   j=j/4096;
   j=j*40000;
   i=j;
   return i;
   }