Yamaha RX21 - Manual (Page 47)

PLAY INSTRUMENT KEYS TO ENTER PATTERN. USE ACCENT KEY
TO ENTER ACCENTS, CLEAR KEY PLUS INSTRUMENT KEY TO CLEAR
MISTAKES.
Step Write (Example: 4/4 Time, Quantize Rate 16, on pattern 00)
PLAY INSTRUMENT KEYS TO ENTER MORE NOTES. USE ACCENT KEY TO
ENTER ACCENTS, +1/YES KEY TO ENTER RESTS, CLEAR KEY PLUS IN-
STRUMENT KEY TO CLEAR MISTAKES.
Dot Display (Example: Time 3/4, Quantize 1/16, on pattern 00)
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