写入注册，回读和比较不工作

Question

我正在写一段C代码，我将一些值写入寄存器（来自i2c器件），从寄存器读回值并比较值是否相同。它看起来像这样：

typedef struct
{
   uint8      address;  //address of the i2c slave register
   uint8      value;    // value which have to be written into the register
} messages;


messages *pMsg;

void write_to_i2c( uint8 address, uint8 value)
{
   i2c_Instance()->DTR  = address;     //DTR is the Data Transmit Register     of i2c
   i2c_Instance()->DTR  = value;
}

uint8 read_from_i2c( uint8 address )
{
   i2c_Instance()->DTR  =  address;
   return  i2c_Instance()->DTR);
}


write_to_i2c( pMsg->address, pMsg->value )

tempReadback = read_from_i2c( pMsg->address); //write the read value into a variable

if (tempReadback == pMsg->value) //compare if the written value is the same as the read value
{
   return OK;
}

else
{
   return NOT_OK
}

到目前为止，好的。函数void write_to_i2c将消息写入i2c寄存器。消息是i2c从器件的寄存器地址和必须写入寄存器的值。

功能＆＃34; read_from_i2c＆＃34;只读回写入i2c从设备寄存器的值。当我调试代码时，我可以在寄存器中看到正确的值，但每次都在else循环中结束。所以，问题是：我将这些值与正确值进行比较的方式是什么？