24C512问题，高手来救我啊，一个星期没想明白

我的程序是先存4个数到24c512的四个地址里，然后读出到液晶上显示，结果读出来的都是FF。有IIC DEBUGER看是：
S A0 A 24 A 00 A 0B A P
S A0 A 78 A 01 A 0B A P
S A0 A 78 A 02 A 0B A P
S A0 A 78 A 03 A 0B A P
S A0 A 08 A 00 A Sr A1 A FF N P
S A0 A 08 A 01 A Sr A1 A FF N P
S A0 A 08 A 02 A Sr A1 A FF N P
S A0 A 08 A 03 A Sr A1 A FF N P
下面是部分程序，请大家帮下忙了，弄了好几天了，郁闷死了。
StoreData(0,11);
StoreData(1,13);
StoreData(2,15);
StoreData(3,17);

aaa=ReadData(0);
bbb=ReadData(1);
ccc=ReadData(2);
ddd=ReadData(3);

void StoreData(uint Address,uchar Value)
{
start();
shout(FM_WRITE);
// shout(Address);
shout(Address/256); shout(Address%256);
shout(Value);
stop();
delayms(10);
}

uchar FM_read_current()
// 在当前地址读取
{
uchar read_data;
start();
shout(FM_READ);
read_data = shin();
SendAck(1); //因为只读一个值，所以发送非应答位。
stop();
return(read_data);
}

uchar ReadData(uint Address)
{
start();
shout(FM_WRITE);
// shout(Address);
shout(Address/256); shout(Address%256);
return(FM_read_current());
}