Connecting two pressure sensors with one uno I'm trying to connect two BMP180s to an arduino uno by using a multiplexer.

Here is the code that a guy has written before:
I imported SFE_BMP180 library but didn't do anything with the "typedef.h" thing.

I'm getting "Data does not name a type" error at the line 9.
How can  I solve this problem?

     #include &lt;SFE_BMP180.h&gt;
    #include &lt;Wire.h&gt;
    #include "typedef.h"

    #define SELECT_PIN 9
    #define ALTITUDE 510.0

#define P1_ACTIVE digitalWrite(SELECT_PIN,HIGH); //delay(10);
#define P2_ACTIVE digitalWrite(SELECT_PIN,LOW);  //delay(10);

SFE_BMP180 bmp1,bmp2;
boolean readSensors(Data *data1, Data *data2);

Data newData(char id)
{
  Data d ; 
  d._id = id ;
  return d ;
}
void setup()
{
    boolean failed = false ;
    pinMode(SELECT_PIN, OUTPUT);

    Serial.begin(9600);

    P1_ACTIVE

    if(bmp1.begin()){
        Serial.println("BMP #1 init success.");
    }
    else 
          failed = true ;


    P2_ACTIVE
    if(bmp2.begin()){
          Serial.println("BMP #2 init success.");
    }
    else 
        failed = true ;

    if(failed){
        Serial.println("Error in BMP180 init.");
        while (1);
    }
}

void loop()
{
  Data d1 = newData('1');
  Data d2 = newData('2');

  boolean read = readSensors(&amp;d1,&amp;d2);


  if(read){
          /* print the value to serial terminal */
...
You can try my BMP080/BMP180 Arduino library
My library doesn't require use of floats of math library, making your sketch very small and fast.