edf8e16c_NC_USB_HID_interface_component__Description
[USB Data Type] Output Value > 1 Bit [Common Usage] Multi-Colour LED [Description] 
The Generic HID device can support bi-colour and tri-colour LEDs, which is how these devices are set. Only a simple integer output is supported at this time.
hidcomp - EMC/LinuxCNC USB HID interface component
Description