An explanation for a function selected for a help display is displayed in text on a display screen, and a light-emitting element disposed to correspond to a switch for performing the selected function is operated to blink or light, so that the trouble of finding an operation element when a desired function...http://www.google.co.uk/patents/US20010025558?utm_source=gb-gplus-sharePatent US20010025558 - Function guide in electronic musical instrument
