All Sound Off (78H); Reset All Controllers (79H); Mode Message; All Notes Off (7Bh) - Casio AP-200 Manual

Send
This message is never sent.
Receive
Receipt deselects RPN.
9.18

All Sound Off (78H)

Format
Message Format: BnH 78H 00H
n: MIDI Channel Number
Send
This message is never sent.
Receive
Receipt stops all voices that are sounding.
9.19

Reset All Controllers (79H)

Format
Message Format: BnH 79H 00H
n: MIDI Channel Number
Send
This message is sent when the keyboard channel is changed and when the recorder function is used.
Receive
Receipt initializes each performance controller.
10

Mode Message

10.1

All Notes Off (7BH)

Format
Message Format: BnH 7BH 00H
n: MIDI Channel Number
Send
This message is sent when the keyboard channel is changed and when a Music Library or recorder operation is performed.
Receive
Receipt of any of this message releases the currently sounding voice (same as releasing the keyboard key).
17