Roland UM-4 Owner's Manual page 38

Appendices
FreeMIDI Users on Macintosh
If you connect multiple UM-4 units and make FreeMIDI settings (P.30), multiple "UM-4
Port" items will appear in step 3 (P.31), as shown in the illustration. Check all of them, and
click [OK]. Then follow the procedure to continue making settings.
fig.04FUKUSU_Mac2.e
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