145Prophet X User’s GuideAppendix E: MIDI ImplementationNRPN MessagesThe Non-Registered Parameter Number (NRPN) MIDI messages areused to transmit and receive both global and program parameters. Theyare transmitted when MIDI Parameter Send is set to NRPN in globals,and received when MIDI Parameter Receive is set to NRPN in globals.The messages are handled in standard MIDI format using the NRPN CCcommands in running status byte format. Below is the format used fortransmitting a NRPN parameter.Transmitted NRPN MessagesStatus Description1011 nnnn Control Change0110 0011 NRPN parameter number MSB CC0vvv vvvv Parameter Number MSB0110 0010 NRPN parameter number LSB CC0vvv vvvv Parameter Number LSB0000 0110 NRPN parameter value MSB CC0vvv vvvv Parameter value MSB0010 0110 NRPN parameter value LSB CC0vvv vvvv Parameter value LSBThe parameter number can be found in the two tables below, one forglobal parameters, and the other for program parameters. The parameternumbers and the parameter values are broken into two 7-bit bytes forMIDI transmission; the LSB has the seven least-significant bits, and theMSB has the seven most-significant bits, though in most cases the MSBwill be zero or one, and never more than two.When receiving an NRPN, all messages do not necessarily need to betransmitted, since the synth will track the most recent NRPN number,though it is usually good practice to send the entire message above.Once an NRPN is selected, the synth will also respond to NRPN DataIncrement 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 forresetting the currently selected parameter to a known state.
