How many pic pins for a sensor

[watchme]

Hi all,
I am building a robot and i would please like to know
how many sensors can i use with a 40 pin pic? For example, how do i find out how many pins will i need for this sensor(  http://www.robotshop.com/sfe-acs712-low-current-sensor-breakout.html  ) ?
Thank you very much

[waltr]

The data sheets will have that information.

Click on the "useful Links for the data sheet and schematic for the sensor.

Which 40 pin PIC? You can download the data sheet from Microchip.
The number of digital IO and analog pins vary on different 40 pin PICs.
The answer would also depend on what peripherals in the PIC you use.