????????#include?
????????#include?
????????#include?
????????#include?
????????#include?
????????#include?
????????#include?
????????#include?
????????#define?I2C_RETRIES?0x0701
????????#define?I2C_TIMEOUT?0x0702
????????#define?I2C_RDWR?0x0707?
????????/*********定義struct?i2c_rdwr_ioctl_data和struct?i2c_msg，要和內(nèi)核一致*******/

struct?i2c_msg
????????{
????????????????unsigned?short?addr;
????????????????unsigned?short?flags;
????????#define?I2C_M_TEN?0x0010
????????#define?I2C_M_RD?0x0001
????????????????unsigned?short?len;
????????????????unsigned?char?*buf;
????????};

struct?i2c_rdwr_ioctl_data
????????{
????????????????struct?i2c_msg?*msgs;
????????????????int?nmsgs;?
????????/*?nmsgs這個數(shù)量決定了有多少開始信號，對于“單開始時序”，取1*/
????????};

/***********主程序***********/
????????int?main（）
????????{
????????????????int?fdretk;
????????????????struct?i2c_rdwr_ioctl_data?e2prom_data;
????????????????fd=open（“/dev/i2c-0“O_RDWR）;
????????/*
????????dev/i2c-0是在注冊i2c-dev.c后產(chǎn)生的，代表一個可操作的適配器。如果不使用i2c-dev.c
????????的方式，就沒有，也不需要這個節(jié)點。
????????*/
????????????????if（fd<0）
????????????????{
????????????????????????perror（“open?error“）;
????????????????}
????????????????e2prom_data.nmsgs=2;?
????????/*
????????*因為操作時序中，最多是用到2個開始信號（字節(jié)讀操作中），所以此將
????????*e2prom_data.nmsgs配置為2
????????*/
????????????????e2prom_data.msgs=（struct?i2c_msg*）malloc（e2prom_data.nmsgs*sizeof（struct?i2c_msg））;
????????????????if（!e2prom_data.msgs）
????????????????{
????????????????????????perror（“malloc?error“）;
????????????????????????exit（1）;
????????????????}
????????????????ioctl（fdI2C_TIMEOUT2）;/*超時時間*/
????????????????ioctl（fdI2C_RETRIES2）;/*重復次數(shù)*/
????????????????/***write?data?to?e2prom**/

????????????????e2prom_data.nmsgs=1;
????????????????（e2prom_data.msgs[0]）.len=27;?//1個?e2prom?寫入目標的地址和1個數(shù)據(jù)?
????????????????（e2prom_data.msgs[0]）.addr=0x51;//e2prom?設(shè)備地址
????????????????（e2prom_data.msgs[0]）.flags=0;?//write
????????????????（e2prom_data.msgs[0]）.buf=（unsigned?char*）malloc（27）;
????????????????（e2prom_data.msgs[0]）.buf[0]=0x00;//?e2prom?寫入目標的地址
				for?（k=1;k<27;k++）		
????????????????（e2prom_data.msgs[0]）.buf[k]=（unsigned?char）k;//the?data?to?write?

????????		ret=ioctl（fdI2C_RDWR（unsigned?long）&e2prom_data）;
????????????????if（ret<0）
????????????????{
????????????????????????perror（“write?error“）;
????????????????}

				free（（e2prom_data.msgs[0]）.buf）;
????????????????sleep（1）;

				
????????/******read?data?from?e2prom*******/
??	????????????e2prom_data.nmsgs=2;
????????????????（e2prom_data.msgs[0]）.len=1;?//e2prom?目標數(shù)據(jù)的地址
????????????????（e2prom_data.msgs[0]）.addr=0x51;?//?e2prom?設(shè)備地址
????????????????（e2prom_data.msgs[0]）.flags=0;//write
				?（e2prom_data.msgs[0]）.buf=（unsigned?char*）malloc（1）;
????????????????（e2prom_data.msgs[0]）.buf[0]=0x00;//e2prom數(shù)據(jù)地址
????????????????（e2prom_data.msgs[1]）.len=26;//讀出的數(shù)據(jù)
????????????????（e2prom_data.msgs[1]）.addr=0x51;//?e2prom?設(shè)備地址?
????????????????（e2prom_dat