1: Press A for 2 seconds to open,and another 2 seconds to shut down(no matter what modes the device is in).
2: Pree B for 2 seconds,you can switch between Chord table mode and Circulation mode.
3: When it is in Chord table mode,Area display of chord name and display of fingering chart in light,area display of metronome and chords number in darkness.
4:When it is in circulation mode,Area display of chord name and display of fingering chart all in light.