Yamaha QY 300 Owner's Manual page 121

In the normal edit mode
only the first 8 bytes of
the exclusive data will
appear on the display, and the
data cannot be edited (only in-
serted or deleted).
"Excl": Exclusive
This event allows 16-byte exclusive data blocks (first byte = "F0") to be
inserted in the sequence data to control external MIDI devices as required.
Move the cursor to any of the data byte locations following the initial "F0"
byte and use the [-1/NO] and [+1/YES] keys of the data dial to enter as
required. Since the data is entered in hexadecimal format, the numeric keypad
cannot be used.
Enter the Specified Event
Press the [ENTER] key to enter the event as specified. A click will be heard as
the event is entered.
Return to the Change Edit Mode
Press the [F6] function key ("Exit") to return to the change edit display, and
continue editing as required.
Exit From the Edit Mode
Press the [F6] function key ("Exit") to exit from the change edit mode and
return to the normal SONG or PHRASE play mode.
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