Lexicon MPX 1 - MIDI IMPLEMENTATION DETAILS User manual

MPX 1
MIDI Implementation Details

Lexicon, Inc. • 3 Oak Park • Bedford MA 01730-1441 • Tel: [phone] • Fax: [phone]
© 1997, Lexicon, Inc.
All Rights Reserved
Lexicon Part No. 070-11835 Printed in U.S.A.

Overview ..................................................................1
Data Formatting....................................................1
Message Tables ...................................................2
System Control .....................................................3
Parameter Types.............................................3
Messages........................................................4
Request •System Configuration
Parameter Description • Parameter
Type • Data Transfer
“Learning” the MPX 1 ...........................................4
Building a Parameter Description
Database...................................................4
Building the Control Tree ................................5
Using the Information ...........................................7
An MRC-type Controller ..................................7
A Glass Interface Controller ............................9
Device Inquiry..........................................................9
Message Classes ..................................................10
00 System Configuration Message.....................10
Number of Parameter Types.........................11
Bottom Parameters .......................................11
01 Parameter Data Message..............................11
02 Parameter Display Message .........................13
03 Parameter Type Message .............................14
04 Parameter Description...................................15
Parameter Type Number...............................15
Number of Parameter Name Characters ......15
Parameter Name...........................................16
Number of Bytes ...........................................16
Control Flags.................................................16
Options Parameter Type ...............................16
Number of Units/Limits..................................16
Minimum Value .............................................16
Maximum Value ............................................16
Display Units Type ........................................17
Requesting the Parameter Description .........17
05 Parameter Label Message ............................17
06 Requests .......................................................18
12 Handshaking..................................................19
16 Database Dump.............................................20
18 Report Effect Parameters ..............................21
19 Report All Effect Parameters .........................22
1A Program Information .....................................23
1B Program Dump..............................................24
Parameter Data.............................................26
LFOs through Envelopes ..............................28
Contents
Sort Flags......................................................28
Audio Routing................................................29
Rules.......................................................31
Algorithm Numbers .......................................32
Program Name..............................................32
Effect Status..................................................33
Knob Data .....................................................33
Patch System Data .......................................33
Soft Values....................................................35
Tempo ...........................................................35
Tempo Source...............................................36
Beat Value.....................................................36
Tap Source....................................................36
Tap Average..................................................36
Tap Source Level ..........................................36
Meter .............................................................36
Master Level..................................................37
Master Mix.....................................................37
Requesting a Program Dump........................37
1C Compact Program.........................................37
Parameters.............................................................37
Unique Parameters.............................................37
MIDI Speed ...................................................37
Panel Button Message ..................................37
Rate...............................................................38
Dumps ................................................................39
All LEDs Dump ...................................................39
Display Dump .....................................................41
Custom Character Bitmap Dump........................41
Setup Dump........................................................42
Global Patches Dump.........................................45
Bypass Controllers Dump...................................46
Remap Controllers Dump ...................................46
Current Choices Dump .......................................47
Patches Dump ....................................................51
Soft Row Dump ..................................................51
Units ................................................................52
Appendix A: Controller Indeces ..........................53
Master List of Controllers....................................54
Global Patch Controllers.....................................54
Bypass Controllers .............................................55
Appendix B: Display Units ...................................56
Appendix C: Glossary of Terms ..........................57
Appendix D: Known Bugs ....................................58

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MPX 1 MIDI Implementation Details
Lexicon
MPX 1
MIDI Implementation Details
ASCIItextversionsofthisdocument,theMPX1ControlTreeandMPX1ParameterDescriptionsare
available on CompuServe under section seven of the MIDI B forum. To access these documents:
• Enter CompuServe, type GO MIDIBVEN
• Select "section seven: Lexicon"
• Enter the Lexicon library
Overview
This document defines the System Exclusive (SysEx) MIDI implementation used in the Lexicon MPX 1,
and assumes familiarity with the functions and operations of the MPX 1.
Data Formatting
With the exception of message headers (first 5 bytes) and “end of SysEx” messages (the last byte in the
message), all data is transmitted in a nibble-ized format, i.e. each byte of data is transmitted asa pair of
bytes, with 4 bits of data in each byte.
Asinallothercasesin theMPX1,theless-significantportionofthebyteistransmittedfirst.16-bit"words"
(2bytes)are sentlow nibble of the lowbyte, followedby high nibble ofthe low byte,low nibble of the high
byte, then high nibble of the high byte.

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Message Tables
Throughout this document, SysEx messages are shown as Message Tables to provide a consistent
method of describing the contents of each message class. The tables are organized into rows of related
groups of bytes and columns containing the attributes of each field. For example, the System Configu-
ration message table is defined as follows:
Transmit only
Byte # Byte Value Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127
5 00 System Configuration
6-7 0n Major Version (1 byte) The number that appears to the left of the decimal point on
the power up display. Example: V1.00
8-9 0n Minor Version (1 byte)
The first column indicates the Byte # of a particular field.
Thesecondcolumnindicatesthebytevalue.Thisvalueisgenerallypresentedinhex,butmayalsoappear
in binary. In some cases the value is a fixed number (for example: Lexicon ID) while others may vary.
Values that can change are represented using a combination of numbers and letters. Binary numbers,
forinstance,arerepresentedusingalowercase“b”foreachvariablebitinthevalue(forexample:Device
ID: 0bbb bbbb). The “b”s can represent 1s or 0s. Hex numbers which can use different numbers in the
lower nibble are represented by a lower case “n” which can represent any hex number between 0 and F.
Althoughonlyasingle“0n”isindicatedintheValuecolumnforcertainfields,thesefieldswilloftenconsist
of multiple bytes (each of which uses the format: 0n). This is due to nibble-ization, and to the fact that a
singlefieldcandescribeagroupofmorethan1byte(strings,forexample).Inthesecases,theDescription
column will generally indicate the number of bytes of un-nibble-ized data contained in the field.

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System Control
All external control is performed using parameters. These parameters are broken down into a two
dimensional inverted tree not unlike the directory structure of a computer disk. Each controllable
parameterin the system (as well as the system itself) is assigneda specific Control Address that defines
its position in the tree. Each System Control Address is defined by a series of Control Levels. The size
(number of control levels) of a given parameter’s Control Address varies depending on its position. The
following diagram shows a portion of the MPX 1 tree with one full branch. (Letters are used to define
System Control levels.)
The parameter which defines the product itself sits at the top of the tree with, essentially, a null control
address (no control levels).
Control levels ->
ABCDEFGHI
|||||||||
MPX 1 0- Program
0- Pitch
0- Detune (M)
0- Mix 0-100%
1- Level
2- Tune
...
1- Chorus
0- Chorus Algorithm
0- Mix
1- Level
2- EQ
...
1- System
0- Audio Config
1- Setup
...
The address of “Program” is A:0, while the address of Detune is A:0, B:0, C:0. Detune’s “Level” is A:0,
B:0, C:0, D:1and Detune’s “Tune” is A:0, B:0, C:0, D:2. The address of the Chorus Algorithm’s “Level”
isA:0,B:1,C:0,D:1while “Audio Config” would beat A:1,B:0.The numberof controllevels increases as
you move to the right in the tree. Each control address in the system that contains a parameter is refered
to as a “node”.
Note that the Control Address is used to identify a specific parameter — including the MPX 1 itself. The
"parameter"whichdefinestheMPX1 isatthetopofthetreewithanullControlAddress(nocontrollevels).
Parameter Types
MPX 1system softwarecontains an indexed listof parameter typesrepresentingeach unique parameter
in the system. The parameter type defines all attributes of the parameter (name, number of bytes, etc.)
except itsposition inthe treewhich is definedby its Control Address. Several parameters can be defined
asthesameparametertype.Forexample,eachMixparameterineachalgorithmintheMPX1isthesame
parametertype,buthasadifferentControlAddress.Conversely,allSystemControlAddresseswhichare
accessible have a single parameter type assigned to them.

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LexiconMPX 1 MIDI Implementation Details
Messages
UsingControlAddressesandParameterTypes,several SysExmessageshavebeendefined toallowan
external system to learn to control and interface with another MPX 1. Five core messages are typically
used: Request
System Configuration
Parameter Description
Parameter Type
Data Transfer
These five messages make up a basic toolkit for communicating with the MPX 1. Each message type is
given an identifying number.
Request
TheRequest message consitutes anexternal requestmadeto anMPX 1to respondwith one oftheother
message types. The Request consists of the identifying number of the message you want returned and,
any specific information the system requires to respond properly.
System Configuration Message
This message provides basic information about the target system such as software revision, date of
release and number of parameter types supported by the particular system.
Parameter Description Message
EachparametertypeintheMPX1hasa“description”thatprovidesinformationabouttheparametersuch
asitslegalvalues.Acontrollingsystemtypically“requests”theSystemConfigurationMessagetofindout
how many parameter types the system supports, then requests the Parameter Description for each
parameter.Alocaldatabaseofparameterdescriptionsinthecontrollingsystemisusedtobuildthecontrol
tree and to edit parameters.
Parameter Type Message
After a database of parameter descriptions has been built of all parameter types, the controlling system
needs to find out what the control tree for the MPX 1 looks like and what parameter type is used at each
“node” ofthe tree. To do this, the controlling system “requests” the Parameter Type fora specific Control
Address.
Data Transfer Message
Afterthe parameter type ata given control address isknown, theData Transfer Messageis used to send
parameter change valuesto the MPX 1or to “request” the currentvalue.The Parameter Descriptiontells
you the name and legal values of the parameter.
“Learning” the MPX 1
In order for a controlling system to control or interface with the MPX 1, it needs information such as the
Manufacturer ID, the Product ID and the Device ID of the system. The Manufacturer ID and the Product
ID can be acquired using the Non Real-Time System Exclusive General Information Device Inquiry. The
Device ID can be obtained from the system’s user interface or by using “all devices” (127).
Building a “Parameter Description” Database
Building a control tree and editing parameters requires information about parameter types. The external
control system requests the “System Configuration Message” to tell it how many “types” the system
supports, then requests a description of each parameter. As each parameter description comes in, the
control system builds a database with them. Refer to the Parameter Description (04 hex) for additional
information about the elements of this database.

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Building the Control Tree
Oncethecontrollingsystemknowsthenumberofparameterstypesthesystemsupports,itneedstoknow
the position of each in the control tree. The Parameter Type message is used to find the location in the
tree of any parameter type. When you want to find out what parameter type is at a particular control
address, you “request” the Parameter Type Message using the Control Address as arguments to the
Requestmessage. TherequestforatypicalControlAddressisshownbelow.Notethatthe“NumControl
Levels”and the actual Control Address(eg -“Level Avalue”) fieldsare 16-bitvalues ina nibble-ized form
with the least significant nibble coming first.
request Num Control Level A Level B
——header—— class levels value value
F0 06 09 00 06 0300020000000000000001000000F7
“06” isthe message class for the request (un-nibble-ized), “03” is the message classyou are requesting
(Parameter Type Message), “2” is the number of control levels in the Control Address, “0” is the value of
level ‘A’ of the Control Address and “1” is the value of level ‘B’ of the Control Address (or A:0, B:1). This
would be “Chorus” in the following tree fragment:
Control levels ->
ABCDEFGHI
|||||||||
MPX 1 0 - Program
0 - Pitch
0 - Detune (M)
0 - Mix 0-100%
1 - Level
2 - Tune
...
1 - Chorus
0 - Chorus Algorithm
0 - Mix
1 - Level
2 - EQ
...
1 - System
0 - Audio Config
1 - Setup
...
The top of the control tree is a sort of “null” Control Address which doesn’t contain any control levels. It
is requested as follows:
request Num Control
——header—— class levels
F0 06 09 00 06 03 00 00 00 00 00 F7
The message indicates 0 control levels but the MPX 1 responds with the parameter type at the top of the
tree. The parameter types are represented as numbers in the Parameter Type Message which comes
back from the MPX 1. This number (0x0155) is then used as an index into the database of parameter
descriptions created earlier. Building the control tree always starts by requesting the parameter type at
the top of the tree.

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Once you have access to the description of the parameter at the top of the control tree, the description
contents is used to build the tree below it. Each of the descriptions contains a “min” value and a “max”
value. For parameters such as “Mix” that can be edited, these are the maximum mix value (100) and the
minimum mix value (0) to which the parameter can be set. When the parameter type is not an editable
parameter, the min and max represent the tree branches below it. A parameter is considered editable if
the “Control Level” flag in the parameter description Control Flags field is NOT set (see Parameter
Description (04 hex). For these parameter types the min value is always 0 and the max value is always
thenumberofbranchesbelowit,minus1.Theminandmaxvaluesrepresenttheminimumandmaximum
branch (level value) that can be accessed below it. In the case of the top level parameter, the max value
is the largest level ‘A’ Control Address value allowed.
When the controlling system knows how many level ‘A’ parameters are allowed, it can work with those
branches. In the MPX 1, it the max value under the top level parameter type is 1. This means that level
“A” can be 0 or 1. The controller would then request the parameter “type” at control address A:0 (A = 0)
as follows:
request Num Control
——header—— class levels level A
F0 06 09 00 06 03 00 01 00 00 00 0000 00 00 F7
The MPX 1 would send back the parameter type at that Control Address (0x0153, the “Program”
parameter). In the MPX 1, this parameter has a max value of 19. This means that control addresses A:0
B:0 through A:0 B:19 are legal so you can request parameter types for these addresses. In the next
request you would go one level deeper:
request Num Control
——header—— class levels level A level B
F0 06 09 00 06 03 00 02 00 00 00 0000 00 00 0000 00 00 F7
The MPX 1 system would send back the parameter type at that control address (0x014D, the “Pitch”
parameter). In the MPX 1, this parameter has a max value of 10. This means that control addresses A:0
B:0 C:0 through A:0 B:0 C:10 are legal so you can request parameter types for these addresses.
This continues deeper and deeper into the control levels (letters) until you reach an actual editable
parameter. At this point you have reached the end of the branch so you go to the next value of that level.
In the MPX 1, the entire first branch looks like this:
Control level
ABCDEFGHI
|||||||||
MPX 1 0- Program
0- Pitch
0- no effect
0- Mix

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When you hit the “Mix” parameter, you are at the end of the branch so you would go to the next address
under “no effect” which is “Level”.
Control level
ABCDEFGHI
|||||||||
MPX 1 0- Program
0- Pitch
0- no effect
0- Mix
1 - Level
The “no effect” parameter has a maximum value of 1 so you would back up to the next value of
“Pitch” which is “Detune (M)” (A:0, B:0, C:1).
Control level
ABCDEFGHI
|||||||||
MPX 1 0- Program
0- Pitch
0- no effect
1 - Detune (M)
The description shows a maximum value of 3, meaning that control addresses A:0 B:0 C:1 D:0 through
A:0 B:0 C:1 D:2 are legal. This procedure continues until you hit the bottom of the tree.
In each parameter’s description, there is a field called “control flags”. This is a bit-mapped value that,
among other things, tells you if a parameter is a “branch” or an editable parameter. If the control flag is
set to 1, there are more parameters beneath it. If the bit is set to 0, the parameter is editable and there
are no parameters beneath it.
Note that all of the numbers in these requests except the message class must be 16-bit values so they
must each be sent as 4 nibble-ized bytes.
Using the information
In many ways, the implementation of MPX 1 SysEx will differ depending on the system in which it is
implemented. A personal computer, for instance, can present more information at one time to the user
than a hand held remote control. The personal computer also has a much larger memory capacity (for
holding onto databases, etc.) than the remote. On the other hand, a program running on a personal
computer may not want to tie up memory with information about connected equipment or provide more
than a simple interface to the box. All of these issues effect how a particular program will use LUSP to
control a system.
Please note that these are hypothetical implementations only.
An MRC-type of Controller
A simple implementation on a system like the Lexicon MRC would not have enough internal memory
to hold much information about the connected system at any given time so it would have to request
information of the system as needed.
The MRC only has 4 faders so only 4 parameters could be accessed at any given time. The faders
and their associated buttons would either allow you to navigate through the control tree or actually
change a parameter value. The MACH button on the MRC could be designated as an <Esc> key to
back you up towards the top of the tree while the faders and buttons drop you down into the tree
(fader selects the branch, button drops you down in).

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LexiconMPX 1 MIDI Implementation Details
For example, for the MPX 1, part of the tree looks like this:
System Control level
ABCDEFGHI
|||||||||
0- Program
0- Pitch
0- Detune (M)
0- Mix
1- Level
2- Tune
3- P Dly
1- Detune (S)
...
2- Detune (D)
...
3- Shift (M)
...
1- Chorus
...
2- EQ ...
3- Modulation
...
4- Reverb
...
5- Delay
...
Initially, the MRC display would simply show the name of the connected product which it retrieves by
requestingtheParameterTypeatthetopofthetree.OncetheParameterTypeisknown,arequestissent
for adescription of the parameter which would include the name of the parameter (in this case “MPX 1”,
thetop level parameter).The description alsoincludesa minimumand maximum valuefor theparameter
which would be used to select branches to drop down into.
Thiscurrentlyhasamaximumvalueof1sorequestsaremadefortheParameterTypesatSystemControl
Addresses 0 and 1. Requests are sent for descriptions of the two Parameter Types. The name strings in
the returning messages are used to display the choices, one over each fader: “Program” and “System”.
When a labeled fader is moved, the MRC isends a Parameter Data Message to the connected system
followed by a request for the Parameter Display Message for the parameter. This produces a formatted,
textversionofthecurrentparametervalue.Pressingthebuttondropsyoutothenextlevel.Inthisexample,
let’s assume we’ve selected the “Program” branch. In the above diagram “Program” has 6 items under
it: Pitch, Chorus, EQ, Modulation, Reverb and Delay. Moving the “Program” fader we would see “Pitch”,
“Chorus”,“EQ”,“Modulation”,“Reverb”or“Delay”displayed.Thestringswouldbeacquiredbysettingthe
“Program” parameter value and requesting a Parameter Display message.
If the “Program” button is pressed, the system requests the Parameter types of the first four branches
under “Program”: “Pitch”, “Chorus”, “EQ” and “Modulation”. The names from each description are
displayedoverthefourfaders.PressingtheMRC’sPAGEbuttonwouldgetthenextfouritemsifavailable,
eventually wrapping backaround tothefirst four.As thefaders are moved, theParameterData Message
is sent and Parameter Display message is requested to display the selection.
The previous process is repeated until the “Branch” bit of the “Control Flags” of a parameter description
isencounteredsetfor0.(Parameterswiththatbitsetto0actuallychangetheoperationofthesystemand
signal the end of a branch. The previous parameters only provide navigation through the tree.)

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A Glass Interface Controller
Aglassinterface(personalcomputer,etc.)couldtakeaslightlydifferentapproach.Withagraphicdisplay
capability and memory (both program and data) to spare, a glass interface can provide more direct and
visually stimulating access to the MPX 1. The glass interface has the option of deriving the tree structure
fromtheMPX1duringaninitializationphaseoroflearningthetreestructureoncethenhard(orsemi-hard)
codingthe Control Addressesto theglass interface elements. Thetree structurecould still belearned via
MIDI but it would only be used to build a road map into the tree.
BecauseallaspectsoftheinterfaceuseacommonSysExmessage(ParameterDataMessage),theglass
interface programmer can concentrate on presentation and organization of the information instead of
merely accessing it. Communication traffic could be reduced by doing a one-time build of a parameter
description database.
Asasidenote,theuserinterfacesoftwareintheMPX1usesbothhardandsoftcodedControlAddresses
to edit parameters within the box itself.
Device Inquiry
The MPX 1 supports Non-Real Time System Exclusive General Information “Device Inquiry” as defined
in the “MIDI 1.0 Detailed Specification 4.2”. When the MPX 1 receives the following message: F0 7E
<channel>0601F7(where<channel>isthedevice IDoftheconnectedMPX1), theMPX1willrespond
with the following message:
0xF0, 0xFE <channel> Universal System Exclusive Non-real time header
0x06 General Information (sub-ID#1)
0x02 Identity Reply (sub-ID#1)
0x06 Lexicon’s System Exclusive ID code
0x00, 0x00 Device Family Code
0x09, 0x00 Device Family Member Code (MPX1)
0x0n Major Software Version number
0x0n Minor Software Version number
0x0n Software Development Phase
0x00 unused
0xF7 EOX

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LexiconMPX 1 MIDI Implementation Details
Message Classes
MPX 1 System Exclusive uses message types defined as Message Classes. The Message Class
identifier appears just after the standard SysEx header (Start of SysEx: F0, Company ID, Product ID,
Device ID) and defines how the remaining data should be interpreted. The following message classes
have been defined for the MPX 1:
# Hex Description
00 System Configuration Message
01 Parameter Data
02 Parameter Display
03 Parameter Type
04 Parameter Description
05 Parameter Label
06 Requests
12 Handshake
16 Database Dump
18 Effect Parameters
19 All Effect Parameters
1A Program Stats
1B Program Dump
1C Compact (Preset) Program Dump
00 System Configuration Message
The System Configuration Message provides a method for extracting information about the software in
the system from the box via SysEx. As such, this message can only be requested from the system and
will be ignored if sent to the system.
Transmit only
Byte # Value HEX Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127
500 System Configuration
6-7 0n Major Version (1 byte) The number that appears to the left of the decimal
point on the power up display. Example: V1.00
8-9 0n Minor Version (1 byte) The number that appears to the right of the decimal
point on power up display. Example: V1.00
10-25 0n 8-character Time string (8 bytes) Time of the code build in ASCII format: xx:yy:zz
xx = Hour
yy = Minute
zz = Second
Example: 17:51:03
26-47 0n 11-character Date string (11 bytes) Date of the code build in ASCII format: xxx:yy:zzzz
xxx = Month
yy = Day
zzzz = Year
Example: May 10 1996
48-51 0x01C0 #of parameter types (2 bytes) Total number of parameter types in the MPX 1.
52-55 0x0164 “Bottom” parameter # (2 bytes) Last system control parameter in a branch before
an editable parameter.
56-59 0x0005 #of Control Levels used (2 bytes) Maximum number of control levels used by the
system
60 F7 End of Sysex

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Number of Parameter Types
The Number of Parameter Types message specifies the number of parameter types in the MPX 1. An
editor programcan use this torequestParameter Description (04 hex) dumps ofall theparameters inthe
system.
Bottom Parameters
A Bottom parameter is the last control level on a given branch and indicates that there is only one lower
level—theonewhichcontainsthereal,adjustableparameters.WiththeexceptionofEffectcontrollevels,
all otherparameters areused only to navigatetheuser interface. (Effectcontrol levelscan besent values
to change the currently running algorithm.)
RatherthanidentifyingBottomparameters,acontrollingsystemcansimplymonitortheControlLevelflag
in the Parameter Description to identify the end of a branch ( bit/flag cleared).
The remaining information can be used by the controlling system to detect software updates and to
ascertain the ROM version.
There are no arguments to the System Configuration Request. The Request message is as follows
(assuming the Device ID is 0): Req
——header—— Class ——unused———
F0 06 09 00 06 00 00 00 00 00 00 00 00 F7
|
Device ID (0-126)
01 Parameter Data Message
This message allows all types of parameter data to be passed to and from the system. Typically this
message class is used to change parameter values in a system remotely (automation, etc) and to dump
datainandoutofthebox.Theword“parameter”shouldbeinterpretedlooselyhereasMPX1parameters
can be actual dumps as well as traditional parameters such as mix, reverb time, etc.
Transmit + Receive only
Byte # Value HEX Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127 transmit, 0-126 receive
501 Message class Parameter data
6-9 0n Number of bytes (2 bytes) Numberofbytesintheparameteranditsoption,ifavailable.
This is a 16-bit field so up to 64K bytes is supported.
10-x 0n Parameter data Actualparameterdataand,ifavailable,optiondata.Option
data always appears after the parameter data. Use the
number of bytes field of the parameter and the option
description to differntiate the parameter from the option.
— 0n # of control levels (2 bytes) Number of control levels are used in the parameter ad-
dress. This is a 16-bit field so the address can have up to
64k digits (control levels). (MPX 1 max is 5.)
— 0n Control level 0 (A) (2 bytes) Thisisthefirst controllevel.It definesthelevel 0(A) control
address of the parameter. The control level addresses are
16bitfieldssothecontroladdressescanbe64kdeep.Note
that letters are used to differentiate levels and theirvalues.
— 0n Control level 1 (B) (2 bytes) same as previous
— 0n Control level 2 (C) (2 bytes) same as previous
— 0n — up to Control level 65535 same as previous
F7 End of Sysex

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Note that the “data” includes any Option data associated with the parameter. For example a 16-bit
parameter with an 8-bit option would contain 3 bytes of data. The Parameter Type of both the parameter
and its option must be used to correctly interpret the “data” in this message.
Control Levels are used in the request message for this packet as follows:
0n Number of Control Levels (lo nib) (Nibble 1 of argument)
0n Number of Control Levels (lo mid nib) (Nibble 2 of argument)
0n Number of Control Levels (hi mid nib) (Nibble 3 of argument)
0n Number of Control Levels (hi nib) (Nibble 4 of argument)
0n Control Level 0 (A) (lo nib) (Nibble 5 of argument)
0n Control Level A (lo mid nib) (Nibble 6 of argument)
0n Control Level A (hi mid nib) (Nibble 7 of argument)
0n Control Level A (hi nib) (Nibble 8 of argument)
0n Control Level 1 (B) (lo nib) (Nibble 9 of argument)
0n Control Level (lo mid nib) (Nibble 10 of argument)
0n Control Level (hi mid nib) (Nibble 11 of argument)
0n Control Level B (hi nib) (Nibble 12 of argument)
To request Program - EQ - 1 Band (M) - Gain (control address A:0, B:2, C:1, D:2) on a system with the
Device ID set for 0, send: request Num Control
——header—— class levels
F0 06 09 00 06 0100 0400 00 00
Level A Level B Level C Level D
(Program) (EQ) (1 Band (M)) Gain)
0000 00 00 0200 00 00 0100 00 00 0200 00 00 F7
A typical return message is as follows:
Number of Number of Control
——header—— data bytes data levels
F0 06 09 00 01 01 00 00 00 00 00 04 00 00 00
Level A Level B Level C Level D
0000 00 00 0200 00 00 0100 00 00 0200 00 00 F7
Torequest a displaydump (controladdressA:1,B:8,C:1)on asystem withtheDevice IDset for0, send:
request Num Control Level A
——header—— class levels (System)
F0 06 09 00 06 0100 0300 00 00 0100 00 00
Level B Level C
(Panel) (Display)
0800 00 00 0100 00 00 F7
A typical return message is as follows:
Number of
——header—— data bytes data—>
F0 06 09 00 01 00 02 00 00 00 02 02 05 06 07 02 06 00 00
data—>
0D 04 09 06 08 07 00 02 00 02 00 02 0C 04 05 06 06 07
05 06 0C 06 0C 030E 03 00 02 00 02 00 02 00 02 00 02
00 02 00 02 05 02 00 02 00 02 00 02 00 03 04 06 02 04
# control lvls Level A Level B Level C
03 00 00 00 01 00 00 00 08 00 00 00 01 00 00 00 F7

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MPX 1 MIDI Implementation Details
Lexicon
02 Parameter Display Message
This message allows you to display parameter values based on what they actually do instead of the
numbers that represent them in the stored data structures. This is particularly useful for system
parameters which generally have text strings stored in the internal ROM to describe the values.
Transmit only
Byte # Value HEX Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127
502 Parameter Display Message class
6-9 0n # of characters (2 bytes) Number of characterss (bytes) in the string
10-x 0n String characters “Number of characters” of nibble-ized ASCII characters
— 0n # of control levels (2 bytes) Number of control levels are used in the parameter ad-
dress. This is a 16-bit field so the address can have up to
64k digits (control levels)
— 0n Control level 0 (A) (2 bytes) Thisisthefirstcontrollevel.Itdefinesthelevel0(A)control
address of the parameter. The control leveladdresses are
16-bit fields so the control addresses can be 64k deep.
Letters are used to differentiate levels and their values.
— 0n Control level 1 (B) (2 bytes) same as previous
— 0n Control level 2 (C) (2 bytes) same as previous
— 0n — up to Control level 65535 same as previous
F7 End of Sysex
Control Levels are used in the request message for this packet as follows:
0n Number of Control Levels (lo nib) (Nibble 1 of argument)
0n Number of Control Levels lo mid nib) (Nibble 2 of argument)
0n Number of Control Levels (hi mid nib) (Nibble 3 of argument)
0n Number of Control Levels (hi nib) (Nibble 4 of argument)
0n Control Level 0 (A) (lo nib) (Nibble 5 of argument)
0n Control Level A (lo mid nib) (Nibble 6 of argument)
0n Control Level A (hi mid nib) (Nibble 7 of argument)
0n Control Level A (hi nib) (Nibble 8 of argument)
0n Control Level 1 (B) (lo nib) (Nibble 9 of argument)
0n Control Level B (lo mid nib) (Nibble 10 of argument)
0n Control Level B (hi mid nib) (Nibble 11 of argument)
0n Control Level B (hi nib) (Nibble 12 of argument)
To request Program - EQ - 1 Band (M) - Gain (control address A:0, B:2, C:1, D:2) on a system with the
Device ID set for 0, send:
request Num Control Level A
——header—— class levels (Program)
F0 06 09 00 06 0200 04 00 00 00 00 00 00 00
Level B Level C Level D
(EQ) (1 Band (M)) (Gain)
02 00 00 00 01 00 00 00 02 00 00 00 F7
The number of characters varies with Parameter Type, the arguments and the actual value of the
parameter.

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LexiconMPX 1 MIDI Implementation Details
03 Parameter Type Message
This message is transmitted from the system in response to a request for Parameter Type at a specific
Control Address. This allows external equipment to build a control tree of the system by requesting the
parameter at an address, checking its description to identify it as a Control Level or an adjustable
parameter. (Control Levels indicate at least one lower level.)
Transmit only
Byte # Value HEX Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127
503 Message Class Parameter Type
6-9 0n Parameter Type (2 bytes) 0x0000-0x01BF (see list)
10 F7 End of Sysex
Control Levels are used in the request message for this packet as follows:
0n Number of Control Levels (lo nib) (Nibble 1 of argument)
0n Number of Control Levels (lo mid nib) (Nibble 2 of argument)
0n Number of Control Levels (hi mid nib) (Nibble 3 of argument)
0n Number of Control Levels (hi nib) (Nibble 4 of argument)
0n Control Level A (lo nib) (Nibble 5 of argument)
0n Control Level A (lo mid nib) (Nibble 6 of argument)
0n Control Level A (hi mid nib) (Nibble 7 of argument)
0n Control Level A (hi nib) (Nibble 8 of argument)
0n Control Level B (lo nib) (Nibble 9 of argument)
0n Control Level B (lo mid nib) (Nibble 10 of argument)
0n Control Level B (hi mid nib) (Nibble 11 of argument)
0n Control Level B (hi nib) (Nibble 12 of argument)
TorequesttheParameterTypenumberforProgram-EQ-1Band(M)-Gain)onasystemwiththeDevice
ID set for 0, send:
request Num Control Level A
——header—— class levels (Program)
F0 06 09 00 06 0300 04 00 00 00 00 00 00 00
Level B Level C Level D
(EQ) (1 Band (M)) (Gain)
02 00 00 00 01 00 00 00 02 00 00 00 F7

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MPX 1 MIDI Implementation Details
Lexicon
04 Parameter Description
Each parameter type used by the system is assigned a unique identifying number, much like menus and
dialog boxes are assigned IDs in Windows and Macintosh software. As these numbers represent the
attributes of a parameter, each can be used for several parameters. An example of this is the audio Mix
parameter type used in all MPX 1 algorithms. The Mix parameter itself is different for each algorithm, but
as each uses the same parameter type, only one parameter description is necessary.
Typically, this message is requested once for each legal parameter type creating a database of all
parameter descriptions to build a control tree.
Transmit only
Byte # Value HEX Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127
504 Message Class Parameter description
6-9 0n Parameter Type (2 bytes) max 65536 types
10-11 0n # of Characters in Name (1 byte) max 255 characters
12 - n 0n Name of parameter
(# of characters nibbled) ASCII (as some LCDs use 0-7 for custom characters. 0,
should not be interpreted as the end of the string)
0n # of bytes (2 bytes) Size of the parameter (max 65535 bytes)
0n Control Flags (1 byte) Hex Binary
00 0000 0000=No flags set
01 0000 0001=Automation
02 0000 0010=Patchable
03 0000 0011=Automation & Patchable
04 0000 0100=Control Level
08 0000 1000=Bottom Control Level
0n Option Parameter Type (2 bytes) Uses standard Parameter Type numbers. Note that a
value of 0xFFFF indicates no options are used.
0n Number of units/limits (1 byte) max 255 units/limits
0n 1st Minimum Value (2 bytes)
0n 1st Maximum Value (2 bytes)
0n 1st Display units (2 bytes) see below
0n 2nd Minimum Value (2 bytes)
0n 2nd Maximum Value (2 bytes)
0n 2nd Display units (2 bytes)
0n nth Minimum Value (2 bytes)
0n nth Maximum Value (2 bytes)
0n nth Display units (2 bytes)
F7 End of Sysex
Parameter Type Number (Bytes 6-x)
This is the ID of this parameter type. Each actual parameter in the system is assigned a Parameter Type
Number to describe its operation.
Number of Parameter Name Characters (Bytes 10-11)
ThisidentifiesboththenumberofcharactersinthenameandthepointatwhichtheParameterNamefield
ends and the Number of bytes field begins. Not all parameter names are of the same size; audio
parameters tend to have 5-character names, while most others have 11 characters.

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LexiconMPX 1 MIDI Implementation Details
Parameter Name (Bytes 12-x)
This is the actual text string used to describe the parameter. Note that this string is NOT null terminated
but will often be padded with spaces (ASCII 20 hex). In most cases, these are the strings that appear on
thefrontpaneldisplay.Parametertypeswiththesamenamesoftenhaveotherattributesthataredifferent.
Number of Bytes
This is the size of the parameter in bytes. Most parameters are 1 or 2 bytes. Parameters that are bigger
includethe“Program”name,the“Setup”nameandother“dump”parameters.Thoughnotreflectedinthis
number,the data bytes forparameter Options are included indata messagesfor parameters which have
options. When dealing with Parameter Data messages, the Parameter Description for the option
parameter must be referenced to correctly interpret the data (number of bytes in the option Parameter
Type, min/max value, etc.).
Note that some Option parameter types (Rate units, Drate units, etc.) actually have 0 bytes. In these
parameters,the “data” is actually contained in the MSB of theroot parameter’sdata. Refer to the Unique
Parameters section for additional information.
Control flags
The control flags are used to define several attributes that are either on or off (0=NO, 1=YES). The
following bits have been defined for the MPX 1:
Bit Mask Description
0 0x01 Patchable
1 0x02 Automation (transmitted when automation is turned on)
2 0x04 Control level
3 0x08 Bottom Control Level (the last control level before an editable parameter)
Options Parameter Type
ThisdefinestheParameterTypeNumber(ID)oftheparameter’soptionifitexists.Optionsareessentially
extensions of the parameter itself. Though they have their own types, they are accessed through the
parameters. (See the Parameter Data Message.) Often the option data value must be evaluated before
a parameter value can be correctly interpreted (“Delay” units, for instance). A value of 0xFFFF indicates
that no option parameter is used.
Number of Units/Limits
SomeMPX1parameterscanoperateindifferent“unit”types.AnexampleofthisisDelayTme,whichcan
be set in milliseconds, a ratio of beats per measure relative to the current tempo, feet, meters or tapped
inmilliseconds.Thesystemonlyhasafixedamountofactualdelaymemoryandthestepsofeachofthese
represents different amounts of time so the limits for each are different. This field defines how many unit
typesareavailableforthisparameter.Thisvaluewillalsotellyouhowmanymins,maxs,anddisplayunits
are included in this packet.
If the Numberof Units/Limits is more than 1, theOptionisused to determine whichunit type is used and
what they are called. Use the String version of the Option to get a text description of the current Unit.
Minimum Value
Thisistheminimumallowablevalueforthisparametertype.Notethatthevaluesareexpressedassigned
wordsthatmustbecasttosignedorunsignedbytesiftheparameterisasinglebyteparameter.Alsonote
thatthe minand max valuesareonly meaningfulfor 1and 2byte parameters.Typically, the minand max
fields are defaulted to 0x0000 and 0xFFFF respectively for “dumps”.
Maximum Value
This is the maximum allowable value for this parameter type.

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MPX 1 MIDI Implementation Details
Lexicon
Display Units Type
This field specifies a specific display type for this parameter type. Like parameter types, display types
define a display technique that can be used for more than one parameter type.
Requesting the Parameter Description
A parameter description is requested by specifying the parameter type. For example, to request
parameter 125 hex on a system with the Device ID set for 0, the following message would be sent:
request parameter parameter
——header—— class number
F0 06 09 00 06 0400 05 02 01 00 F7
Note that all 4 nibbles of the parameter must be sent padded with 0s if needed.
05 Parameter Label Message
This message allows you to get a string describing the parameter at a given control level. This message
was included to simplify navigation of the control tree when the controlling system has limited memory
available. The string returned is the same as the “name” field of the parameter description message.
Transmit only
Byte # Value HEX Description Notes
1 F0 Sysex ID (Start)
2 06 Lexicon ID
3 09 MPX 1 ID
4 0bbb bbbb Device ID 0-127
505 Parameter Label Message class
6-9 0n # of characters Number of characters (bytes) in the string
10-x 0n Parameter Label String This is the actual string (nibble-ized) so it is the “Number of
characters” x 2 long
— 0n # of control levels (2 bytes) Numberofcontrol levelsused intheparameteraddress. This
isa16-bitfieldsotheaddresscanhaveupto64kdigits(control
levels)
— 0n Control level 0 (A) (2 bytes) This is the first control level. It defines the level 0 (A) control
addressoftheparameter.Thecontrolleveladdressesare16-
bitfieldssothecontroladdressescanbe64kdeep.Lettersare
used to differentiate levels and their values.
— 0n Control level 1 (B) (2 bytes) same as previous
— 0n Control level 2 (C) (2 bytes) same as previous
— 0n — up to Control level 65535 same as previous
F7 End of Sysex
Control Levels are used in the request message for this packet as follows:
0n Number of Control Levels (lo nib) (Nibble 1 of argument)
0n Number of Control Levels (lo mid nib) (Nibble 2 of argument)
0n Number of Control Levels (hi mid nib) (Nibble 3 of argument)
0n Number of Control Levels (hi nib) (Nibble 4 of argument)
0n Control Level 0 (A) (lo nib) (Nibble 5 of argument)
0n Control Level A (lo mid nib) (Nibble 6 of argument)
0n Control Level A (hi mid nib) (Nibble 7 of argument)
0n Control Level A (hi nib) (Nibble 8 of argument)
0n Control Level 1 (B) (lo nib) (Nibble 9 of argument)
0n Control Level B (lo mid nib) (Nibble 10 of argument)
0n Control Level B (hi mid nib) (Nibble 11 of argument)
0n Control Level B (hi nib) (Nibble 12 of argument)