Is it possible to connect more than two IR speed sensors to Arduino uno ?

Other Hardware Sensors
1

Hi,

I want to measure the speed of 4 wheels with encoder disk
As far as I know, the sensor use IR led and a phototransistor and each time that the photo resistor notify that the light change (aka the encoder disk is spinning) it send interrupt to Arduino that handles the spin event.
The problem is that as far as I know Arduino UNO has only 2 interrupt pins and I need to use 4 pins to measure the speed of 4 individual wheels. There is another way to measure the speed of 4 wheels with ir speed sensor ?

I learn about the sensor from this link:

Thanks

2

All pins can be used to interrupts. Your software must then check which pin generated the interrupt.

3

Could you please give an example ?

As I understand from here in Arduino UNO only pins 2 and 3 can listen to interrupts

Thanks

4

http://playground.arduino.cc/Main/PinChangeInterrupt