Lfos Through Envelopes; Sort Flags - Lexicon MPX 1 - MIDI IMPLEMENTATION DETAILS Midi Implementation Manual

MPX 1 MIDI Implementation Details
It is important to remember that the MPX 1 allows parameters to have "option" values. "Delay Units" for
example, determines the units in which delay time is adjusted (milliseconds, feet, meters, etc...). As
"Delays" are stored in their "Unit" values, it is essential to read the options unit value before operating on
the actual delay setting. Because of this close association of options to their attached parameters, option
data ALWAYS immediately follows the parameter data to which it is associated. In this example, this
means that the 2-byte "delay" parameter becomes a 3-byte parameter.
Continuing the previous example, to access the "P Dly" parameter, you must get past the "Tune"
parameter and it's option parameter value. You will note that, although "Tune" is a 1-byte parameter, its
description structure reveals that it has an option: "Optimize".
pitch parameter data:
0x64 - Mix
0x00 - Level
0x0A - Tune
0x01 - Tune Option
0x00 - P Dly
0x00 - unused
The option parameter itself is identified by a Parameter Type number which we use to access the structure
describing it. The "Optimize" Parameter Description indicates that it is a 1 byte parameter so we increment
the pointer one last time to get to the "P Dly" parameter data.
pitch parameter data:
0x64 - Mix
0x00 - Level
0x0A - Tune
0x01 - Tune Option
0x00 - P Dly
0x00 - unused
Note that not all option parameters are 1-byte. Some have 0 bytes. These are embedded onto the MSB
of the parameter itself.
Other values which may appear in the parameter data packet should be ignored.
LFOs through Envelopes (Bytes 722-843)
The data for the LFOs, Arpeggiator, ADSRs, Random number generator, AB, Sample and Hold and the
Envelope Generators are organized in a similar fashion to the effect parameter data. The only difference
being that there are not multiple algorithms. The parameters for all of these items are always the same.
Otherwise, these parameters are accessed exactly as the effect parameters, including options.
Sort Flags (Bytes 394-399, Parameter Type: 0x0115)
Sort Flags consist of "effect types" (2 bytes) and "input types" (1 byte) (in that order).These define which
to which sorting groups (database) the program will be assigned.
The bit assignments for Effect types are:
PITCH 0x0001
CHORUS 0x0002
EQ 0x0004
MOD 0x0008
DELAY 0x0010
AMBIENT 0x0020
CHAMBER 0x0040
GATE 0x0080
HALL 0x0100
INVERSE 0x0200
PLATE 0x0400
DUAL 0x0800
28
Lexicon