You mean MPC 1000. It's a very capable pattern-based sequencer too in addition to being in the royal family of sampling drum machines.
Read the manual, then hook up the midi out of the Motif to the midi in of the MPC and the midi out of the MPC to the midi in of the Motif --- and this is important --- turn the 'LOCAL' control to off to break the connection between the keyboard and the internal sounds. Then select an empty sequence on the MPC and off you go.
Here are links to two good articles on midi basics - part one and part two. They may be a little too basic for you, but we can all use a refresher course now and then...