Can I use pin for more then one different devices?

Hello,
Can I use only one analog input pin for

  1. GY-521 SCL
  2. temperature sensor
  3. gas sensor

    at same time?

something like example from picture

Do they all use the Wire library (I2C), and if so, what are their addresses?

If they do not use the Wire library, then how will the code determine what sensor its getting data from?

Are you talking about using the pins as analog inputs? In that case, no.

If the pins are being used for I2C, then yes.

HazardsMind: Do they all use the Wire library (I2C), and if so, what are their addresses?

If they do not use the Wire library, then how will the code determine what sensor its getting data from?

if I have attached arduino digital pins 2,3,4... to this devices VCC pins, so if 2 is on and others are off I recieve data from first device,if 3 is on and others are off from second device and so on. Not only I2C devices, for example three I2C devices and four not I2C devices.

You can do that, sure, but the digital pins only provide 40mA of current at 5 volts. How much current do your sensors require to work properly?

lasha_p92: if I have attached arduino digital pins 2,3,4... to this devices VCC pins, so if 2 is on and others are off I recieve data from first device,if 3 is on and others are off from second device and so on. Not only I2C devices, for example three I2C devices and four not I2C devices.

That will create a mess if the boards have built in pull up resistors on SCL and SDA.

HazardsMind: You can do that, sure, but the digital pins only provide 40mA of current at 5 volts. How much current do your sensors require to work properly?

aarg: That will create a mess if the boards have built in pull up resistors on SCL and SDA.

That is the side of electronic, my brother is physicist and I will check it with him, thank you for suggestions :)