HP Princeton HP-21 - Manual (Page 9)

General Guide
1) POWER SWITCH
2) MASTER VOLUME
3) DUAL
4) DSP
5) TOUCH
6) RECORD
7) TRACK A
8) TRACK B
9) REPEAT
10) METRONOME
11) TRANSPOSE +/-
12) TEMPO +/-
13) DEMO ALL
14) RECORD
- PLAY
- STOP
15
）DEMO
- SELECT
- START/STOP
16
）VOICE TYPE & DEMO SONG SELECT
0 - PIANO 1
1 - PIANO 2
2 - E.PIANO 1
3 - E.PIANO 2
4 - HARPSICHORD
5 - VIBES
6 - STRINGS ENSEMBLE
7 - CHORUS
8 - JAZZ ORGAN
9 - CHURCH ORGAN
17
）LED
- TEMPO
- SONG
- TRANSPOSE