Digital Sound & Music: Concepts, Applications, & Science, Chapter 6, last updated 6/25/2013
a SysEx ID number. MSC has a SysEx sub-ID number of 0x02. The syntax, in hexadecimal, for
a MSC message is:
F0 7F device_ID 02 command_format command data F7
is the status byte indicating the start of a SysEx message.
indicates the use of a SysEx sub-ID. This is technically a manufacturer ID that has
been reserved to indicate extensions to the MIDI specification.
can be any number between 0x00 and 0x7F indicating the device ID of the
thing you want to control. These device ID numbers have to be set on the receiving end
as well so each device knows which messages to respond to and which messages to
ignore. 0x7F is a universal device ID. All devices respond to this ID regardless of their
individual ID numbers.
is the sub-ID number for MIDI Show Control. This tells the receiving device that the
bytes that follow are MIDI Show Control syntax as opposed to MIDI Machine Control,
MIDI Time Code, or other commands.
is a number indicating the type of device being controlled. For
example, 0x01 indicates a lighting device, 0x40 indicates a projection device, and 0x60
indicates a pyrotechnics device. A complete list of command format numbers can be
found in the MIDI Show Control 1.1 specification.
is a number indicating the type of command being sent. For example, 0x01 is
“GO”, 0x02 is “STOP”, 0x03 is “RESUME”, 0x0A is “RESET”.
represents a variable number of data bytes that are required for the type of
command being sent. A “GO” command might need some data bytes to indicate the cue
number that needs to be executed from a list of cues on the device. If no cue number is
specified, the device simply executes the next cue in the list. Two data bytes (0x00, 0x00)
are still needed in this case as delimiters for the cue number syntax. Some MSC devices
are able to interpret the message without these delimiters, but they're technically required
in the MSC specification.
is the End of Systems Exclusive byte indicating the end of the message.
Most lighting consoles, projection systems, and computer sound playback systems used in
live entertainment are able to generate and respond to MSC messages. Typically, you don't have
to create the commands manually in hex. You have a graphical interface that lets you choose the
command you're want from a list of menus. Figure 6.41 shows some MSC FIRE commands for a
lighting console generated as part of a list of sound cues. In this case, the sound effect of a
firecracker is synchronized with the flash of a strobe light using MSC.