interfacing with the pulse oximeter...!!

this is the pulse oximeter i m using...!!!
it uses microcontroller MSP430F247T Rev D....
i could detect some signal on pin no 32 of the UC...bt i m not sure if dats right..!!
this is the data sheet i could get..

the problem is how do i program the arduino to take dis data...!!!
i wana pick up the digital signal directly...!!!
plz help...!!!!