JLCooper ES-4/100 MIDI - Manual (Page 11)

Using the ES-4/100 and ES-8/100 with Pro Tools
Some current software packages do not directly support the ES-
4/100 and ES-8/100. You can still use your ES-4/100 and ES-
8/100 with these applications by configuring the software for HUI
operation.
For example, you can configure ProTools to use the ES-4/100 and
ES-8/100 with HUI emulation by selecting Setups | Peripherals
from the main menu.
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