Yamaha SY77 Operating Manual page 89

For example to store your new voice in Internal memory bank C memory
number 16, press
INTERNAL,
Press (Go), and the bottom line will ask "Are you sure ? (Yes or No)". If
F8
you are sure you want to store the edited voice, press
line of the LCD will show "Store completed". If you decide not to store, press
and the bottom line of the LCD will show "Store cancelled".
-1/NO
You will then return to voice play mode.
then then .
C 16
and the bottom
+1/YES
77