Boss Audio Systems BR-900CD User Manual

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MIDI Fundamentals
By using MIDI to connect the BR-900CD to other MIDI-
capable devices, you can perform the following:
● Play rhythm performances on external MIDI sound 
module
● Synchronize with external MIDI sequencers and rhythm 
machines
● Control MMC-compatible devices from the BR-900CD
This section provides a basic description of MIDI and 
explains the various ways it can be used.
What is MIDI?
MIDI stands for “Musical Instrument Digital Interface.” 
MIDI is a global standard devised so that performance data, 
program change data, and other similar information could be 
exchanged among electronic musical instruments and 
computers. If a device is MIDI compatible, it will be able to 
exchange performance data with other MIDI compatible 
devices, even if they are of a different type or brand.
MIDI Connectors
MIDI messages (i.e., the data handled by MIDI) are 
exchanged using the following three types of MIDI port.
MIDI IN:
This connector accepts the MIDI messages arriving from 
other MIDI devices.
MIDI OUT:
All the MIDI messages from the BR-900CD are sent out from 
this connector.
MIDI THRU:
This connector re-transmits all the MIDI messages that arrive 
at the MIDI IN connector.
MIDI Channels
The MIDI standard allows data to be exchanged among 
multiple MIDI-compatible devices using a single MIDI cable, 
and this is made possible by what are known as MIDI 
channels.
In simple terms, a MIDI channel is quite similar to a TV 
channel. For example, you can change TV channels to watch 
programs from a variety of broadcasters. In this type of 
situation, information is communicated only when the 
channel on the transmitting end matches the channel on the 
receiving end. 
Likewise, with MIDI as well, if the transmitting device is (for 
example) set to MIDI channel 1, MIDI messages will be 
received only if the MIDI channel on the receiving end is also 
set to 1.
MIDI Implementation Charts
MIDI makes it possible for a vast range of electronic musical 
devices to communicate with each other. However, this does 
not mean that every MIDI device can handle every single 
type of MIDI message. In reality, two MIDI-compatible 
devices can only exchange the MIDI messages that are 
supported by both.
The user’s manual for any MIDI-compatible device will 
contain a MIDI Implementation Chart, and this chart allows 
you to quickly find out which MIDI messages the device in 
question can transmit and receive. 
When two MIDI devices are to be used together, you should 
compare their MIDI implementation charts to make sure that 
exchange of the required MIDI messages will be possible. 
For more detailed information regarding the BR-900CD’s 
MIDI characteristics, refer to “MIDI Implementation” (p. 216).
The BR-900CD is equipped with a MIDI OUT port, but 
not with MIDI IN and MIDI THRU ports.