user40438: What is a rev id? I have looked everywhere for a proper definition but I haven't found anything. I am trying to understand the code below. I don't understand why this read_rev_id function is necessary and yes, I tried to look in the user manual for the IMU I am using but it is practically none-existent. I am using the myAHRS IMU and the only manual I could find, on GitHub, didn't even show a register by this name. 
void setup()
{
  //Initialization
  Wire.begin();
  Serial.begin(115200);    
  who_am_i();
  read_rev_id();
  delay(1000); //Wait for 1second.
}


user35385: You haven't provided enough information for anyone to easily help you. Assuming that you took your code from GitHub myAHRS_plus_i2c.ino you can look further down the file to find the definition of read_rev_id(). It simply reads the revision number from the AHRS chip and displays it on the console. Since this is all that it does you could leave out the call to read_rev_id(). But if you are going to use it then be aware that it contains an obvious bug. The second read() should be to I2C_SLAVE_REG_REV_ID_MINOR.
//READ REVISION ID
int read_rev_id()
{
    uint8_t id_1 = 0;
    uint8_t id_2 = 0;
    read(I2C_SLAVE_REG_REV_ID_MAJOR, &id_1, 1);
    read(I2C_SLAVE_REG_REV_ID_MAJOR, &id_2, 1);
    Serial.print("READ REVISION ID= "); Serial.print(id_1); Serial.println(id_2);
}


40438: <p>What is a rev id? I have looked everywhere for a proper definition but I haven't found anything. I am trying to understand the code below. I don't understand why this read_rev_id function is necessary and yes, I tried to look in the user manual for the IMU I am using but it is practically none-existent. I am using the myAHRS IMU and the only manual I could find, on GitHub, didn't even show a register by this name. </p>

<pre><code>void setup()
{
  //Initialization
  Wire.begin();
  Serial.begin(115200);    
  who_am_i();
  read_rev_id();
  delay(1000); //Wait for 1second.
}
</code></pre>
 35385: <p>You haven't provided enough information for anyone to easily help you. Assuming that you took your code from GitHub myAHRS_plus_i2c.ino you can look further down the file to find the definition of <strong>read_rev_id()</strong>. It simply reads the revision number from the AHRS chip and displays it on the console. Since this is all that it does you could leave out the call to read_rev_id(). But if you are going to use it then be aware that it contains an obvious bug. The second <strong>read()</strong> should be to I2C_SLAVE_REG_REV_ID_MINOR.</p>

<pre><code>//READ REVISION ID
int read_rev_id()
{
    uint8_t id_1 = 0;
    uint8_t id_2 = 0;
    read(I2C_SLAVE_REG_REV_ID_MAJOR, &amp;id_1, 1);
    read(I2C_SLAVE_REG_REV_ID_MAJOR, &amp;id_2, 1);
    Serial.print("READ REVISION ID= "); Serial.print(id_1); Serial.println(id_2);
}
</code></pre>
