LUSP Messages
In order to make use of the "Control Addresses" and "Data Types", several SysEx messages have been defined which allow an external system to learn how to control and interface with a LUSP compatible system. There are 5 core messages you typically use:

1. A Request Message

2. A System Configuration Message

3. A Data Description Message

4. A Data "Type" Message

5. A Data Transfer Message

These make up a basic toolkit for learning and communicating with a LUSP compatable system. Each message type is given a number that the protocol uses to identify it.

Request Message

The "Request" message allows an external system to make inquiries of the LUSP system. You "request" that the system send you back one of the other message types. The "request" message consists of the message "number" you want back and, usually, some specific information that the system needs to properly answer your "request".

System Configuration Message

This message provides basic information about the LUSP compatable system. The information includes software revisions, date of release and most importantly, the number of "Data Types" supported by the particular system.

Data Description Message

For each "data type" supported by a particular LUSP system, there is a "description" that provides information about the "Data Type". A controlling system typically "requests" the "System Configuration Message" to find out how many "Data Types" the system supports, then requests the "Data Description" for each "Data Type". A local database of Data Type "description"s in the controlling system which it uses to build the control tree and to edit the "Data" (parameters, dumps).

Data "Type" Message

After a database of Data Type "descriptions" has been built of all "Data Types" supported by the LUSP system, the controlling system needs to find out what the control tree for the LUSP system looks like and what "Data Type" is used at each "node" of the tree. To do this, the controlling system "requests" the "Data Type Message". The "Data Type Message" reports the "Data Type" at a specified control address (you ask: whats the "Data Type" at address x, LUSP system responds: data type y). More on building the tree below.

Data Transfer Message

After you know the "Data Type" at a given control address, you use the "Data Transfer Message" to send data change values to the LUSP system or "request" the current value of them. The "description" of the data type tells you the name of the data type and it's legal values.