Supply voltage is 3.3v or 5v, I have tried both. I removed resistor and now I am getting 1v and no any changes from dark to light.
Between pin 1(gnd) and pin 2(voltage) I am getting supply voltage depending on source. What makes me feeling odd is if I am not contacting pin 3 to digital input, then voltage is 0v, but no short circuit between pin1 and pin3.