You need to clock (syncronize) it via midi and record it to an audio track.
First, put the Emu in external clock mode. Then run a midi cable from the midi out of your protools interface to the midi in of the Emu. Then run protools and they should be sync'd together.
As far as the audio goes there are two ways to do it. The first is to patch the audio outputs straight into your audio interface and record it to an audio track. The second way leaves the sounds and the sequence that the Emu is running until the final mix, and it requires some kind of mixing board. Plug the outputs of both the protools interface and the Emu into channels on the mixer, then compose your song, THEN put the drums down onto the audio tracks of protools. The second method lets you make sound and rhythm decisions up until the very last minute.
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