Synchronizing MIDI device in Cubase 6


I am using an AKAI LPK25 keyboard with Cubase 6 and would like the arpeggiator in the LPK25 to synchronize with the tempo of my project in Cubase. After setting the Arp clock to External in the LPK25 Editor I’m at loss what to do. Does anyone know what should be done in Cubase?

tell Cubase to send MIDI clock to the MIDI port that is connected to your hardware