tester.c

在linux中arm9对温度传感器18B20进行的驱动开发

#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>

using namespace std;
int main()
{
/* 打开端口 */
	int hHandle = open("/dev/rpt1820",O_RDWR);
	if( hHandle < 0 )
	{
		cout<<"端口打开失败!"<<endl;
		return 1;
	}
    // --------------------------------------------------------------------------------
	
	char uiWBuf = 0;
	static double read_value;
	int cnt =0;
	int mid_data;
	int mid_value;
	static double temp_value;


	int  iRBuf;
	//while( 1 )
	while((cnt++) < 10 )
	{
		int nRead = read(hHandle,&iRBuf,10);
		sleep(1);
		nRead = read(hHandle,&iRBuf,11);
		if( nRead < 0 )
		{
			cout<<"端口读失败!"<<endl;
			break;
		}
		else
		{
			mid_value = (iRBuf & 0xFFFF) >> 4;
			temp_value = (float)mid_value;
			temp_value = temp_value + ((float)(iRBuf & 0x0F)) * 0.0625;
			printf("temp_value = %f\n",temp_value);
		}
		
	//	sleep(3);
	}
    // --------------------------------------------------------------------------------
	close(hHandle);
	return 0;
}