HID = Human Interface Device

HID is the protocol used for the software interface.

If you find that XP is not recognizing the interface, try going into

Control Panel/Administrative Tools/Services

and START the "HID input service".

Once it's started plug in the interface cable to the USB port on the computer.

Sometimes this will cure the problem.

XP should then recognize the new HID device.

Finally plug in the TX and calibrate the new "joystick" device that XP has detected.