Dave Smith Instruments PROPHET 12 DESKTOP - Manual (Page 73)

61 Prophet 12 Module Operation Manual MIDI Implementation
NRPN Messages
The Non-Registered Parameter Number (NRPN) MIDI messages are used to
transmit and receive both global and program parameters. They are transmitted
when MIDI Parameter Send is set to NRPN in Global, and received when MIDI
Parameter Receive is set to NRPN in Global.
The messages are handled in standard MIDI format using the NRPN CC
commands in running status byte format. Below is the format used for transmit-
ting a NRPN parameter.
Transmitted NRPN Messages
Status Description
1011 nnnn Control Change
0110 0011 NRPN parameter number MSB CC
0vvv vvvv Parameter Number MSB
0110 0010 NRPN parameter number LSB CC
0vvv vvvv Parameter Number LSB
0000 0110 NRPN parameter value MSB CC
0vvv vvvv Parameter value MSB
0010 0110 NRPN parameter value LSB CC
0vvv vvvv Parameter value LSB
The parameter number can be found in the two tables below, one for Global
parameters, and the other for Program parameters. The parameter numbers and
the parameter values are broken into two 7-bit bytes for MIDI transmission; the
LSB has the seven least-significant bits, and the MSB has the seven most-signifi-
cant bits, though in most cases the MSB will be zero or one, and never more than
two.
When receiving a NRPN, all messages do not necessarily need to be transmit-
ted, since the synth will track the most recent NRPN number, though it is usually
good practice to send the entire message above.
Once a NRPN is selected, the synth will also respond to NRPN Data Increment
and Decrement commands, which some controllers utilize. Finally, it responds
to one RPN (Registered Parameter Number) command, the RPN/NRPN Reset
command, which can be handy for resetting the currently selected parameter to a
known state.