extern bit ack;
//起動總線函數(shù)
extern void Start_I2c();
//結(jié)束總線函數(shù)  
extern void Stop_I2c();
//應(yīng)答子函數(shù)
extern void Ack_I2c(bit a);
//字節(jié)數(shù)據(jù)發(fā)送函數(shù)
extern void  SendByte(unsigned char  c);
//有子地址發(fā)送多字節(jié)數(shù)據(jù)函數(shù)               
extern bit ISendStr(unsigned char sla,unsigned char suba,unsigned char *s,unsigned char no) ;
//無子地址發(fā)送多字節(jié)數(shù)據(jù)函數(shù)   
extern bit ISendStrExt(unsigned char sla,unsigned char *s,unsigned char no);
//無子地址讀字節(jié)數(shù)據(jù)函數(shù)               
extern unsigned char RcvByte();
 
 
extern void HC595SendData(unsigned int SendVal);