Casio LK-270 MIDI Implementation - Page 32

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 IPR → ← IPS Operation Send Request (Optional) 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 "Part VI Parameter Set List" for details about Instrument parameter sets. 32