Casio CTK-900 Midi Implementation Manual page 42

Data Receiver
BDS →
← BSY
Data Receiver
HDR →
← BSY
Data Receiver
HDS →
← BSY
The same packet is resent when a checksum mismatch or incompatible data structure error is detected.
Data Sender
(Send Canceled)
Data Sender
(Send Canceled)
Data Sender
(Send Canceled)
Operation
Data Send
Busy
Operation
Send Request
Busy
Operation
Data Send
Busy
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