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System messages also come in a number of varieties.
SYSTEM REALTIME messages are used to start, stop and
synchronize the sequencing devices in a MIDI system.
SYSTEM EXCLUSIVE messages allows for the transmission of
data specific to individual devices. This data can be either
individual parameter settings, which are transmitted as
PARAMETER CHANGE messages, or large blocks of settings,
which are usually referred to as BULK DUMPS.
When using the P-200’s MIDI functions, you will be mainly
concerned with channel voice messages and system exclusive
messages. For detailed information about other types of
messages the P-200 supports, and how their corresponding
functions are implemented, refer to the MIDI Data Format and
MIDI Implementation Chart sections.
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Using MIDI
MIDI is an acronym that stands for Musical Instrument Digital
Interface, an international standard in use since the 1980s for
the purpose of allowing electronic musical instruments—such
as synthesizers, tone generators, rhythm programmers, digital
keyboards like the P-200, and others—to “communicate” with
each other by sending and receiving compatible note,
controller and other MIDI data.
With MIDI, instruments made by different manufacturers can
easily be connected to each other using special MIDI cables,
and configured to work together in a variety of ways that
greatly expands your music composing, performing and even
learning capabilities.
Following is an outline of the basic concepts about MIDI you’ll
need to know to get up and running in short order. Also
included are a few examples of MIDI system connections.
MIDI Channels
The MIDI standard provides 16 different channels for the
transmission of data between musical instruments. A MIDI
KEYBOARD is capable of transmitting data on at least one of
these channels. Sequencers and MIDI-equipped computers
with music sequencing software (both of which are generally
capable of recording, editing and playing back MIDI note,
controller and other data) usually transmit data on several
channels at once, each channel being designated for a
different part of an ensemble performance. For example, a
Piano part might be assigned to channel 1, a bass part to
channel 2, a horn part to channel 3, and so on.
MIDI devices known as TONE GENERATORS, which are
literally synthesizers without a keyboard, can receive MIDI data
from keyboards, sequencers, or computers and produce
sounds in response. MULTITIMBRAL tone generators can play
more than one voice at a time, since they can receive data on
more than one channel at a time.
MIDI Messages
Data which is transmitted between MIDI devices takes the
form of MIDI messages. There are various types of messages.
Messages most closely associated with the actual
performance of music are called CHANNEL VOICE messages;
these include NOTE ON and NOTE OFF messages, which tell
a tone generator which notes to play, and when to start and
stop playing them. CONTROL CHANGE, PITCH BEND, and
AFTERTOUCH or key pressure messages indicate how a
keyboard’s control functions are being operated. PROGRAM
CHANGE messages tell a tone generator to switch to another
voice.
Channel voice messages are transmitted on a specific channel
which will be received by the tone generator for which they are
intended. They are different from SYSTEM messages, which
are transmitted on all channels and received by all of the
devices in a MIDI system.
Channel
Messages
System
Messages
VOICE
MODE
Note On/Off, Control Change,
Program Change, Pitch Bend,
Channel Pressure*
All Note Off
REALTIME
Start*/Stop*/Continue*,
Active Sensing
End of Exclusive (F7)
COMMON
EXCLUSIVE
System Exclusive (F0)
*Transmit only.
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