MIDI Messages
MIDI MESSAGES
8n Note Off:
9n Note On:
An Polyphonic Aftertouch:
Bn Control Change:
Cn Program Change:
Dn Channel Aftertouch:
En Pitch Wheel:
F0 System Exclusive:
F7 End Of Exclusive:
(EOX)
F2,F3,F8,FA,FB,FC,FF:
FE Active Sensing:
F1, F4, F5, F9, FD:
The note number indicates which key was released, and velocity indicates how
quickly it was released. Very few keyboards have Release Velocity Sensitivity.
The note number indicates which key was pressed, and velocity indicates how
hard it was hit. On keyboards which do not have a velocity sensitive keyboard,
a medium value of 40 is sent. A Note On message with a velocity of 0 is the
same as a Note Off message.
The note number indicates which key is being pressed, and pressure indicates
how hard that key is being pressed. (i.e., each key can send independent after-
touch messages;)
The control number indicates which controller is being moved, and the data in-
dicates the position of the controller. Continuous controllers (slider or wheel-
type controllers) carry data in the range of 00-7F. Switch-type controllers (eg.
sustain pedal) carry either 00 (off) or 7F (on).
Control changes 7A-7F are called Mode Messages, and usually carry a fixed data
byte. They tell the receiving tone generator how to behave. The way in which
these message are interpreted will depend on the device. (See the MIDI Imple-
mentation Chart for your tone generator or synthesizer.)
This tells the receiving device to switch programs (memories).
Also called “Common After-touch”, this is found on the DX7. It indicates the
strongest pressure on any part of the keyboard, ie, the “common” value.
To provide finer resolution, this data is sent in two bytes, first the Least Sig-
nificant Byte (LSB) and then the Most Significant Byte (MSB). Yamaha tone
generators and synthesizers ignore the LSB.
After F0 must come an identification number which has been assigned to each
manufacturer. Yamaha’s number is 43. What comes between this message and
F7 (End of Exclusive) is completely up to each manufacturer (but each byte
must be from 00 to 7F). Yamaha uses System Exclusive messages to transmit
voice data, sequence data, rhythm pattern data, bulk memory data of all kinds,
and many other useful things. See the System Exclusive format chart for your
device.
This marks the end of a System Exclusive message.
Song Position Pointer, Song Select, Timing Clock, Start, Stop, Continue, System
Reset are all for controlling sequencers and rhythm machines. See the MIDI Im-
plementation Chart for your device.
If there are no MIDI messages that have to be sent, one of these is sent just to
let the receiving devices know that there is still someone out there. If there have
not been any MIDI messages for longer that 300 msec, the receiving device
assumes that some error has taken place (e.g., a MIDI cable was pulled out by
mistake) and will stop all notes.
These are unused, and reserved for future expansion.
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