Channel Messages; System Messages - Yamaha PortaTone PSR-275 Owner's Manual

MIDI is an acronym that stands for Musical Instrument Digital Interface, which
allows electronic musical instruments to communicate with each other, by send-
ing and receiving compatible Note, Control Change, Program Change and various
other types of MIDI data, or messages.
The PSR-275/273 can control a MIDI device by transmitting note related data and
various types of controller data. The PSR-275/273 can be controlled by the
incoming MIDI messages which automatically determine tone generator mode,
select MIDI channels, voices and effects, change parameter values and of course
play the voices specified for the various parts.
MIDI messages can be divided into two groups: Channel messages and System
messages. Below is an explanation of the various types of MIDI messages which
the PSR-275/273 can receive/transmit.
G Channel Messages
The PSR-275/273 is an electronic instrument that can handle 16 channels. This is
usually expressed as "it can play 16 instruments at the same time." Channel mes-
sages transmit information such as Note ON/OFF, Program Change, for each of
the 16 channels.
Message Name PSR-275/273 Operation/Panel Setting
Note ON/OFF Messages which are generated when the keyboard is played. Each
message includes a specific note number which corresponds to the
key which is pressed, plus a velocity value based on how hard the
key is stuck.
Program Change Voice number (along with corresponding bank select MSB/LSB set-
tings, if necessary).
Control Change Messages that are used to change some aspect of the sound (vol-
ume, etc.).
G System Messages
This is data that is used in common by the entire MIDI system. System messages
include messages like Exclusive Messages that transmit data unique to each
instrument manufacturer and Realtime Messages that control the MIDI device.
Message Name PSR-275/273 Operation/Panel Setting
Exclusive Message Reverb setting, etc.
Realtime Messages Clock, Start/stop operations
The messages transmitted/received by the PSR-275/273 are shown in the MIDI
Implementation Chart on page 68.
MIDI Terminals
In order to exchange MIDI data between multiple
devices, each device must be connected by a cable.
The MIDI terminals of the PSR-275/273 are located on
the rear panel.
MIDI IN Receives MIDI data from another MIDI device.
MIDI OUT Transmits the PSR-275/273's keyboard information as MIDI
data to another MIDI device.
MIDI Functions
• Special MIDI cables (sold sepa-
rately) must be used for connect-
ing to MIDI devices. They can be
bought at music stores, etc.
• Never use MIDI cables longer
than about 15 meters. Cables
longer than this can pick up noise
which can cause data errors.
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