Hello................You can use an in and out regular midi cable connection OR the to host connection to a computer serial port or USB port, but make sure you install the correct Yamaha driver if you use the to host setup.

The weblink below has GREAT Yamaha PSR stuff. http://home7.inet.tele.dk/js/musik/740pages/

This link below has some good info on midi setups http://www.borg.com/~jglatt/tutr/miditutr.htm
http://www.music.eku.edu/faculty/davis/MIDIp2.html