AMX AXB-MIDI User manual

instruction manual
AXlink Bus Controllers
AXB-MIDI
MIDI Interface

AMX Limited Warranty and Disclaimer
AMX Corporation warrants its products to be free of defects in material and workmanship under normal use for
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Table of Contents
i
AXB-MIDI MIDI Interface
Table of Contents
Product Information .................................................................................................1
Installation .................................................................................................................3
Setting the DEVICE DIP Switch ........................................................................................ 3
Preparing Captive Wires for AXlink.......................................................................................... 3
Wiring the AXB-MIDI ......................................................................................................... 3
AXlink data and power connections ......................................................................................... 3
AXlink Wiring Guidelines.......................................................................................................... 4
Wiring AXlink with Optional 12 VDC power supply .................................................................. 4
MIDI cable connectors ............................................................................................................. 5
Replacing the Lithium Battery ........................................................................................... 5
Programming ............................................................................................................7
Send Commands............................................................................................................... 7
IN A and IN B MIDI Signal Routing ................................................................................... 8
MIDI Programming ............................................................................................................ 9
Programming examples ........................................................................................................... 9
Summary of MIDI Messages ........................................................................................... 11

ii AXB-MIDI MIDI Interface
Table of Contents

Product Information
1
AXB-MIDI MIDI Interface
Product Information
The AXB-MIDI MIDI Interface is an Axcess device for pass-through and control of Musical
Instrument Digital Interface (MIDI) protocol signals. This unit can act as a MIDI matrix switcher.
AXB-MIDI decodes and encodes MIDI protocol signals and routes the signals according to the
programming within an Axcess Central Controller. The AXB-MIDI communicates with the Central
Controller AXlink data protocols..
The AXB-MIDI provides MIDI signal pass-through and device control. Processing of MIDI
signaling is instantly visible via four front panel LEDs. A lithium battery provides data backup in
the event of power failure. The unit can be mounted in an electronic rack using an optional AC-RK
Accessory Rack Kit.
FIG. 1 AXB-MIDI - front and rear panel components
AXB-MIDI Specifications
Dimensions (HWD) 1.51" x 5.55" x 5.45" (3.84 cm x 14.10 cm x 13.84 cm)
Enclosure Metal with black matte finish
Power consumption 75 mA @ 12VDC
DIP Switch 8-position DIP switch sets the AXlink address for the AXB-MIDI.
Connectors • Four 5-pin DIN MIDI connectors (IN A, IN B, THRU and OUT).
• 4-pin captive wire connector for AXlink control signaling and power from the
Central Controller.
DEVICE
AXlink
ON
A
IN
B
IN
OUTTHRU
IN A THRU IN B OUT
AXlink
AXP GND AXM
PWR
AXlink Status LED
DEVICE DIP Switch
IN - MIDI B
IN - MIDI A
OUT LED
THRU LED
MIDI A INPUT
MIDI B INPUT
MIDI THRU
MIDI OUT
AXlink connector
Front
Rear

Product Information
2AXB-MIDI MIDI Interface
AXB-MIDI Specifications (Cont.)
Input buffer • 3,072 bytes
Output buffer (AXlink) • 6,143 bytes
Max. Length of
SEND_STRING to device
•64
Max. Length of data packets
from device
•64
LED Indicators • AXlink Status LED (green): Lights to indicate that the AXB-MIDI is
operational and interfacing with the Central Controller (when blinking once
per second).
• IN A LED (red): Lights to indicate that there is MIDI data present on the IN A
connector.
• IN B LED (red): Lights to indicate that there is MIDI data present on the IN B
connector.
• THRU LED (red): Lights to indicate MIDI IN A/B signal passing through
without any changes.
• OUT LED (red): Lights to indicate MIDI data is being transmitted out the OUT
connector (after the AXB-MIDI receives AXlink control commands or MIDI
signals from the Central Controller).
Weight 1 lb. 0.5 oz. (488 grams)
Mounting options Flat surface or Rack mount
Optional Accessories • PS2.8, 12 VDC, 2.8 A Power Supply
• Five-pin DIN MIDI cable
• AC-ARK Accessory Rack Kit

Installation
3
AXB-MIDI MIDI Interface
Installation
Setting the DEVICE DIP Switch
The 8-position DIP switch (see FIG. 1) sets the AXlink device number for the AXB-MIDI. The
device number must match the number assigned in the Axcess software program.
The Device DIP switch example shown in FIG. 2 is set to the factory default setting of 90
(2 + 8 + 16 + 64 = 90).
The AXlink device number range is 1-255, and is set according to the Device DIP switch positions
and their values shown in the following table:
Preparing Captive Wires for AXlink
Use a wire stripper and flat-blade screwdriver to prepare and connect the AXlink captive wires:
1. Strip 0.25 inch off the wire insulation for all four wires.
2. Insert the exposed section of each wire into the appropriate opening on the captive wire
connector according to the wiring diagrams shown in the Installation section of this manual.
3. Using a flat-blade screwdriver, turn the screws clockwise to secure the wire in the connector.
Wiring the AXB-MIDI
The AXB-MIDI requires 12.5 VDC to operate properly. The power can be supplied by the Central
Controller's power supply and AXlink cable or with an optional 12 VDC power supply. The
maximum wiring distance between the Central Controller and AXB-MIDI is determined by power
consumption, supplied voltage, and the wire gauge used for the cable.
AXlink data and power connections
Connect the Central Controller's AXlink connector to the AXlink connector on the rear panel of the
AXB-MIDI (see FIG. 1) for data and 12 VDC power, as shown in FIG. 3.
FIG. 2 DEVICE DIP Switch, shown set to default address setting (90)
Device DIP Switch Settings
Position 12345678
Value 1 2 4 8 16 32 64 128
12345678

Installation
4AXB-MIDI MIDI Interface
AXlink Wiring Guidelines
The following table lists wire sizes and maximum lengths allowable between the AXB-MIDI and
the Central Controller power supply. The maximum wiring lengths are based on 13.5 VDC @ 100
mA available at the Central Controller's power supply output cable end.
If the AXB-MIDI is installed farther away from the Central Controller than recommended, connect
an optional 12 VDC power supply to the AXlink connector on the AXB-MIDI rear panel (see the
Wiring AXlink with Optional 12 VDC power supply section on page 4).
Wiring AXlink with Optional 12 VDC power supply
Connect the Central Controller's AXlink connector to the AXlink connector on the rear panel of the
AXB-MIDI, as shown in FIG. 4.
Use an external 12 VDC power supply when the distance between the Central Controller and
AXB-MIDI exceeds the limits described in Figure 9 or the power supply current capacity cannot
FIG. 3 AXlink wiring
PWR +
AXP/TX
AXM/RX
GND -
PWR +
AXP/TX
AXM/RX
GND -
AXB-MIDI Central Controller
If using power from AXlink, disconnect the wiring from the Central Controller before
wiring the AXB-MIDI.
AXlink Wiring Guidelines
Wire Size Max Wiring Length
18 AWG 1,173.71 ft (357.74 m)
20 AWG 742.57 ft (226.34 m)
22 AWG 462.96 ft (141.11 m)
24 AWG 291.83 ft (88.95 m)
FIG. 4 Wiring AXlink with Optional 12 VDC power supply
PWR (+)
GND (-)
Local +12 VDC power supply
(coming from the PSN power supply)
PWR +
AXP/TX
AXM/RX
GND -
PWR +
AXP/TX
AXM/RX
GND -
AXB-MIDI Central Controller

Installation
5
AXB-MIDI MIDI Interface
accommodate the 75 mA draw of the AXB-MIDI. Make sure to connect the GND and +12 VDC
wire on the AXB-MIDI AXlink connector end. Do not connect the optional +12 VDC power
supply wire to the Central Controller's power supply side of the AXlink connector.
MIDI cable connectors
The four MIDI jacks on the rear panel (IN A, IN B, THRU and OUT) are identical 5-pin DIN type
connectors. FIG. 5 shows the pinout for wiring cables to these DIN connectors. It is recommended
that off the shelf MIDI cables be used. MIDI cable lengths will be determined by physical
placement of the Central Controller, AXB-MIDI, and the equipment providing the MIDI input
protocol.
! Pin 2 (shielded ground) is only connected on the THRU and OUT connectors. It is not
connected on IN A and IN B.
! It is recommended that to maintain signal integrity when connecting to any MIDI device,
cable lengths be no more than 20 feet (6.01 meters).
Replacing the Lithium Battery
A lithium battery (Figure 15), with a life of approximately 5 years, in the AXB-MIDI protects
stored presets if a power loss occurs. The battery is not used when DC power is supplied to the
AXB-MIDI. Write down the replacement date on a sticker or label by adding 5 years to the date of
installation. Then attach it to the bottom of the AXB-MIDI.
Contact your AMX dealer before you replace the lithium battery and verify that they have a current
copy of the Axcess program for your AXB-MIDI. This will avoid any inadvertent loss of data or a
service outage.
FIG. 5 MIDI DIN connector pinout
FIG. 6 Lithium battery and socket
1 - (not used)
2 - shielded ground
3 - (not used)
4 - Signal (+)
5 - Signal ( -)
All control commands in AXB-MIDI memory are lost when the lithium battery is
replaced.

Installation
6AXB-MIDI MIDI Interface
You will need a flat-blade tool (non-conducting) that can be slipped under the lithium battery to pry
it up and out of the socket. The location of the Lithium battery on the circuit board is shown in
FIG. 7.
1. Discharge the static electricity from your body.
2. Unplug all cables from the AXB-MIDI.
3. Remove the five pan-head screws on the top of the AXB-MIDI enclosure.
4. Pull the two enclosure halves apart and set the bottom portion of the enclosure on a flat surface.
5. Locate the battery on the circuit card.
6. Carefully pry the battery out of its socket and insert the new battery. Write down the next
replacement date on a sticker or label by adding 5 years to the replacement date. Then attach it
to the bottom of the AXB-MIDI.
7. Plug all cables back into the AXB-MIDI.
8. Place the top portion of the enclosure back onto the bottom portion. Then, refasten the five
pan-head screws.
9. Reconnect the cables.
Static electricity can damage electronic circuitry. Before removing the lithium battery
from the enclosure, discharge any accumulated static electricity from your body by
touching a grounded metal object.
FIG. 7 AXB-MIDI circuit card, showing location of battery
Battery/socket
rear
front
There is a danger of explosion if you replace the battery incorrectly. Replace the
battery with the same or equivalent type recommended by the manufacturer. Dispose
of used battery according to the manufacturer's instructions. Never recharge,
disassemble, or heat the battery above 212°F (100°C). Never solder directly to the
battery or expose the contents of the battery to water.

Programming
7
AXB-MIDI MIDI Interface
Programming
Send Commands
Send_Commands control AXB-MIDI signal routing by the Central Controller. The AXB-MIDI
supports the Send_Commands described below.
AXB-MIDI Send_Commands
Command Description
INA
Configure the destination for
the incoming data on IN A
(see the IN A and IN B Signal
Routing table on page 8).
Syntax:
'INA-<value>'
Parameter:
<value> = 0 to 7
Example:
SEND_COMMAND <device>,'INA-5'
Routes incoming IN A data to THRU output and to the Central Controller.
INB
Configure the destination for
the incoming data on MIDI
IN B.(see the IN A and IN B
Signal Routing table on
page 8).
Syntax:
'INB-<value>'
Parameter:
<value> = 0 to 7
Example:
SEND_COMMAND <device>,'INB-7'
Routes incoming IN B data to THRU output, OUT output, and transmit data to
the Central Controller.
RXACLR
Clear characters waiting in
the IN A receive buffer (to be
sent to the Central
Controller, MIDI THRU, or
MIDI OUT).
Syntax:
'RXACLR'
Example:
SEND_COMMAND <device>,'RXACLR'
Clears the IN A receive buffer of all contents.
RXBCLR
Clear characters waiting in
the IN B receive buffer (to be
sent to the Central
Controller, MIDI THRU, or
MIDI OUT).
Syntax:
'RXBCLR'
Example:
SEND_COMMAND <device>,'RXBCLR'
Clears the receive buffer contents for IN B.
RXCLR
Clear all characters waiting in
both receive buffers (to be
sent to the Central
Controller, MIDI THRU, or
MIDI OUT).
Syntax:
'RXCLR'
Example:
SEND_COMMAND <device>,'RXCLR'
Clears the receive buffers or all content for IN A and IN B.
RXON
Enable the ABX-MIDI to send
received characters to the
Central Controller.
Syntax:
'RXON'
This command is automatically sent by the Central Controller when a
CREATE_BUFFER program instruction is executed.
Example:
SEND_COMMAND <device>,'RXON'
Sends received characters from IN A and IN B to the Central Controller.

Programming
8AXB-MIDI MIDI Interface
IN A and IN B MIDI Signal Routing
The following table shows all routing value possibilities for IN A and IN B incoming MIDI signals
in relation to the AXB-MIDI rear panel connectors. The value determines where the IN A and IN B
MIDI signals will be routed.
Inputs are controlled as Channels 1 through 8.
AXB-MIDI Send_Commands (Cont.)
Command Description
RXOFF
The AXB-MIDI will not pass
on received characters to the
Central Controller. This is the
default.
Syntax:
'RXOFF'
Example:
SEND_COMMAND <device>,'RXOFF'
Turns IN A and IN B transmit to the Central Controller off.
TXCLR
Clear all characters waiting in
both transmit buffers (MIDI
THRU and MIDI OUT).
Syntax:
'TXCLR'
Example:
SEND_COMMAND <device>,'TXCLR'
Clears THRU and OUT transmit buffers.
TXTHRUCLR
Clear characters waiting in
the MIDI THRU transmit
buffer.
Syntax:
'TXTHRUCLR'
Clear characters waiting in the MIDI THRU transmit buffer.
Example:
SEND_COMMAND <device>,'TXTHRUCLR'
Clears THRU transmit buffer.
TXOUTCLR Syntax:
'TXOUTCLR'
Clears characters waiting in the MIDI OUT transmit buffer.
Example:
SEND_COMMAND <device>,'TXOUTCLR'
Clears OUT transmit buffer of all contents.
IN A and IN B Signal Routing
Value THRU OUT AXlink
0
1X
2X
3XX
4X
5X X
6XX
7XXX
The power-up default value is 3.

Programming
9
AXB-MIDI MIDI Interface
MIDI Programming
Most MIDI command strings consist of a status byte followed by one or two data bytes. The most
notable exception to this is the System Exclusive which starts with a status byte of $F0, has 4 or
more data bytes, then ends with a status byte of $F7. Status bytes are always $80 or greater. Status
bytes are always denoted in hexadecimal. Data bytes are always less than $80 (128 in decimal).
Data bytes may be denoted in either decimal or hexadecimal.
Program change, Control change, and Note On/Off are the most often used of the MIDI "Channel
Voice" commands. Since they are standard MIDI commands they are almost never explained in
manufacturers programming manuals. Program change (Preset), Control change, Note On/Off, and
System Exclusive.
Programming examples
The following section provides some programming examples:
SEND_STRING MIDI,"$C0 + (MIDI_CHANNEL - 1), PROGRAM - 1"
Specific example, to recall preset 128 on MIDI ch 1:
MIDI_CHANNEL = 1
1 - 1 = 0
$C0 + 0 = $C0,
PROGRAM = 128
128 - 1 = 127, thus the send string,
SEND_STRING MIDI,"$C0,127"
The Program change is denoted by status byte $C0 (for MIDI channel 1) through status byte $CF
(for MIDI channel 16), followed by one data byte.
PRGM EX. 1
SEND_STRING MIDI,"$90 + (MIDI_CHANNEL - 1), Note, Velocity" (* Note On *)
SEND_STRING MIDI,"$80 + (MIDI_CHANNEL - 1), Note, Velocity" (* Note Off *)
Note that On is denoted by status byte $90 (for MIDI channel 1) through status byte $9F (for MIDI
channel 16), Note that Off is denoted by status byte $80 (for MIDI channel 1) through status byte $8F (for
MIDI channel 16).
PRGM EX. 2
SEND_STRING MIDI,"$80 + (MIDI_CHANNEL - 1), Note, 0" (* Note Off *)
Most modern controllers send a $90 note on with velocity 0 for note off (We'll save the reason why for
MIDI programming 102).
PRGM EX. 3

Programming
10 AXB-MIDI MIDI Interface
SEND_STRING MIDI,"$B0 + (MIDI_CHANNEL - 1), CONTROLLER, VALUE"
Specific example set volume to 50% on MIDI ch 5:
MIDI_CHANNEL = 5
5 - 1 = 4
$B0 + 4 = $B4,
The standard MIDI Volume controller is 7,
127 * 50% = 64 (approximately), thus the send string,
SEND_STRING MIDI,"$B4, 7, 64"
Selected MIDI controller numbers:
BANK SELECT MSB = 0
VOLUME = 7
PAN = 10
EXPRESSION = 11 (* A SECOND VOLUME CONTROL *)
GENERAL PURPOSE CONTROLLER # 1 = 16
GENERAL PURPOSE CONTROLLER # 2 = 17
GENERAL PURPOSE CONTROLLER # 3 = 18
GENERAL PURPOSE CONTROLLER # 4 = 19
BANK SELECT LSB = 32
HOLD = 64 (* 2nd data byte of 63 or less = OFF,
64 or greater = ON *)
REVERB SEND = 91
EFFECTS 2 DEPTH = 92
CHORUS SEND = 93
EFFECTS 4 DEPTH = 94
EFFECTS 5 DEPTH = 95
ALL SOUND OFF = 120 (* 2nd data byte is always "0" *)
RESET ALL CONTROLLERS = 121 (* 2nd data byte is always "0" *)
The Control change is denoted by status byte $B0 (for MIDI channel 1) through status byte $BF (for MIDI
channel 16), followed by two data bytes.
PRGM EX. 4
MIDI_CHANNEL = 6
6 - 1 = 5
$90 + 5 = $95
Note = 60
Velocity = 96, thus the send string,
SEND_STRING MIDI,"$95,60,96"
To turn the same note off:
SEND_STRING MIDI,"$95,60,0"
Specific example, Middle C (Note #60) on, on MIDI ch 6. If you're not sure what velocity to use try some-
thing between 64 (half) and 127(full), how about 96?
PRGM EX. 5

Programming
11
AXB-MIDI MIDI Interface
Summary of MIDI Messages
The following information refers to MIDI messages and Control Change Messages. The following
table lists and describes Channel Voice messages ([nnnn = 0-15 (MIDI Channel Number 1-16)]):
(* MMC STOP *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$01,$F7"
(* MMC PLAY *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$02,$F7"
(* MMC DEFERRED PLAY *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$03,$F7"
(* MMC FAST FWD *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$04,$F7"
(* MMC REW *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$05,$F7"
(* MMC RECORD STROBE *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$06,$F7"
(* MMC RECORD EXIT *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$07,$F7"
(* MMC RECORD PAUSE *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$08,$F7"
(* MMC PAUSE *)
SEND_STRING MIDI,"$F0,$7F,$7F,$06,$09,$F7"
Most System Exclusives start with $F0, then a three byte system exclusive address, then more data bytes
as determined by the manufacturer, then an end byte of $F7. Unlike the channel voice messages which
are part of the MIDI standard, the system exclusives are usually well explained in the manufacturers
programming manual.
One exception to this is MMC, or MIDI Machine Control. It's part of the MIDI standard. These MMC
commands were captured from a Roland FC-200 MIDI Foot Controller. The address of "$F7,$F7,$06"
means "Universal Realtime Message, Broadcast, MMC". Then there is a single data byte followed by the
end byte $F7.
PRGM EX. 6
Channel Voice Messages
Status (D7---D0) Data Bytes (D7---D0) Description
1000nnnn • 0kkkkkkk
• 0vvvvvvv
• Note Off event.
• This message is sent when a note is released (ended).
• (kkkkkkk) is the key (note) number. (vvvvvvv) is the velocity.
1001nnnn • 0kkkkkkk
• 0vvvvvvv
• Note On event.
• This message is sent when a note is depressed (start).
• (kkkkkkk) is the key (note) number. (vvvvvvv) is the velocity.
1010nnnn • 0kkkkkkk
• 0vvvvvvv
• Polyphonic Key Pressure (Aftertouch). This message is most
often sent by pressing down on the key after it "bottoms out".
• (kkkkkkk) is the key (note) number. (vvvvvvv) is the velocity.
1011nnnn • 0ccccccc
• 0vvvvvvv
• Control Change.
• This message is sent when a controller value changes.
Controllers include devices such as pedals and levers.
• Controller numbers 120-127 are reserved as "Channel Mode
Messages" (below).
• (ccccccc) is the controller number. (vvvvvvv) is the new value
(0-119).

Programming
12 AXB-MIDI MIDI Interface
The following table lists and describes System Common messages:
Channel Voice Messages (Cont.)
Status (D7---D0) Data Bytes (D7---D0) Description
1100nnnn • 0ppppppp • Program Change.
• This message sent when the patch number changes.
• (ppppppp) is the new program number.
1101nnnn • 0vvvvvvv • Channel Pressure (After-touch).
• This message is most often sent by pressing down on the
key after it "bottoms out". This message is different from
polyphonic after-touch. Use this message to send the single
greatest pressure value (of all the current depressed keys).
• (vvvvvvv) is the pressure value.
1110nnnn • 0lllllll
• 0mmmmmmm
• Pitch Wheel Change.
• This message is sent to indicate a change in the pitch wheel.
The pitch wheel is measured by a fourteen bit value. Center
(no pitch change) is 2000H. Sensitivity is a function of the
transmitter.
• (llllll) are the least significant 7 bits. (mmmmmm) are the
most significant 7 bits.
System Common Messages
Status (D7---D0) Data Bytes (D7---D0) Description
11110000 • 0iiiiiii
• 0ddddddd
..
..
• 0ddddddd
• 11110111
• System Exclusive.
• This message makes up for all that MIDI doesn't support.
(iiiiiii) is usually a seven-bit Manufacturer's I.D. code. If the
synthesizer recognizes the I.D. code as its own, it will listen
to the rest of the message (ddddddd). Otherwise, the
message will be ignored. System Exclusive is used to send
bulk dumps such as patch parameters and other non-spec
data. (Note: Real-Time messages ONLY may be interleaved
with a System Exclusive.)
• This message also is used for extensions called Universal
Exclusive Messages.
11110001 • Undefined. (Reserved).
11110010 • 0lllllll
• 0mmmmmmm
• Song Position Pointer.
• This is an internal 14 bit register that holds the number of
MIDI beats (1 beat=six MIDI clocks) since the start of the
song. l is the LSB, m the MSB.
11110011 • 0sssssss • Song Select.
• The Song Select specifies which sequence or song is to be
played.
11110100 • Undefined. (Reserved).
11110101 • Undefined. (Reserved).
11110110 • Tune Request.
• Upon receiving a Tune Request, all analog synthesizers
should tune their oscillators.
11110111 • End of Exclusive.
• Used to terminate a System Exclusive dump (see above).

Programming
13
AXB-MIDI MIDI Interface
The following table lists and describes System Real-Time Messages:
The following table lists and describes Channel Mode messages:
System Real-Time Messages
Status (D7---D0) Data Bytes (D7---D0) Description
11111000 • Timing Clock.
• Sent 24 times per quarter note when synchronization is
required.
11111001 • Undefined. (Reserved).
11111010 • Start.
• Start the current sequence playing. (This message will be
followed with Timing Clocks).
11111011 • Continue.
• Continue at the point the sequence was Stopped.
11111100 • Stop.
• Stop the current sequence.
11111101 • Undefined. (Reserved).
11111110 • Active Sensing.
• Use of this message is optional. When initially sent, the
receiver will expect to receive another Active Sensing
message each 300ms (max), or it will be assume that the
connection has been terminated.
• At termination, the receiver will turn Off all voices and return
to normal (non-active sensing) operation.
11111111 • Reset.
• Reset all receivers in the system to power-up status. This
should be used sparingly, preferably under manual control.
• In particular, it should not be sent on power-up.
Channel Mode Messages
Status (D7---D0) Data Bytes (D7---D0) Description
1011nnnn • 0ccccccc
• 0vvvvvvv
• Channel Mode Messages.
• This the same code as the Control Change (above), but
implements Mode control and special message by using
reserved controller numbers 120-127.
• All Sound Off.
When All Sound Off is received all oscillators will turn
Off, and their volume envelopes are set to zero as soon
as possible.
c = 120, v = 0: All Sound Off
• Reset All Controllers.
When Reset All Controllers is received, all controller
values are reset to their default values.
c = 121, v = x: Value must only be zero unless
otherwise allowed in a specific Recommended Practice.
• Local Control.
When Local Control is Off, all devices on a given
channel will respond only to data received over MIDI.
Played data, etc. will be ignored. Local Control On
restores the functions of the normal controllers.
c = 122, v = 0: Local Control Off
c = 122, v = 127: Local Control On

Programming
14 AXB-MIDI MIDI Interface
Channel Mode Messages (Cont.)
Status (D7---D0) Data Bytes (D7---D0) Description
1011nnnn (Cont.) • All Notes Off.
When an All Notes Off is received, all oscillators will
turn Off.
c = 123, v = 0: All Notes Off
c = 124, v = 0: Omni Mode Off
c = 125, v = 0: Omni Mode On
c = 126, v = M: Mono Mode On (Poly Off) where M is
the number of channels (Omni Off) or 0 (Omni On)
c = 127, v = 0: Poly Mode On (Mono Off)
• (Note: These four messages also cause All Notes Off).

Programming
15
AXB-MIDI MIDI Interface

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