Casio CDP-220R - Manual (Page 29)

19.3.18 EOX : End of System Exclusive Message
Format: 11110111B
This is the End of System Exclusive Message status byte established by the MIDI standard.
20 Individual Parameter Operations
There are two parameter unit operations: Individual Parameter Transfer and Individual Parameter
Request.
For one session, in response to an IPR (Individual Parameter Request) from an external
device, this Instrument returns an IPS (Individual Parameter Send) or the session is concluded when
the external device or this Instrument spontaneously sends an IPS. If this Instrument received an IPS,
the value of the applicable parameter is changed. Depending on the function of a parameter, Individual
Parameter Send may be used to issue a command to the Instrument and Individual Parameter Request
may be used to check Instrument status information.
Data Receiver Data Sender Operation
IPR → Send Request(Optional)
← IPS Data Transfer
21 Parameter Set Transfer
21.1 Communication Modes
21.1.1 One-way and Handshake
In order to ensure maximum speed for bulk dumping of Parameter Sets, the data format is different from
the data format used for Individual Parameter Send. Data is transferred as-is, using the Model’s memory
image. Parameter Sets can be transferred by bulk dump using the message exchange types described
below.
• One-way mode Parameter Set send/receive
• One-way mode Parameter Set send request send/receive
• Handshake mode Parameter Set send/receive
• Handshake mode Parameter Set send request, receive rejected, error notification send/receive
With the one-way mode, the sending device sends data and ends the session without regard to the
response of the receiving device. This mode is best for one-way transfers from a sequencer or similar
device.
With the handshake mode, the sending device sends the data and then waits for a response from the
receiving device before advancing to the next session. This is a high-speed mode in which there is no
time wasted waiting.
See “VI Parameter Set List” for details about Instrument parameter sets.
21.1.2 Session and Subsession
Subsession “One subsession” refers to transfer of one parameter set. A subsession transfers one
parameter set or a parameter set that has been divided into multiple packets for transfer, with EOD
(End of Data) at the end to terminate the send. Division of a parameter set into multiple packets is
used when the size of the parameter set is greater than a prescribed size. The packet number in the
packet index field indicates the sequential position of a packet relative to the other packets. A single
packet cannot be used to transfer multiple small parameter sets. A parameter set delimiter always must
be transferred as a packet delimiter.
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