JLCooper ES-4/100 MIDI - Manual (Page 12)

Select the MIDI Controllers tab.
Select a peripheral and click on HUI. Then, select the MIDI ports
that the ES-4/100 or ES-8/100 is connected to as the Receive From
and Send To ports.
Pro Tools is now configured to use the ES-4/100 or ES-8/100 in
HUI emulation mode. More information can be found in the MIDI
Control Surfaces Guide that came with your Pro Tools system.
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