Overview

This module converts one or two incoming Numerology CV data streams into MIDI NRPN messages. It operates very similarly to CC Gen module. NRPN messages are not supported by all MIDI devices, so you should only be interested in this module if the documentation for your MIDI device (or Audio Unit plugin) instructs you on how to use NRPN message to control it.

A MIDI NRPN message is very similar to a MIDI CC message, but allows for a much larger range of controller numbers, as well as a much wider range of control values. When generating an NRPN message, you have to specify two controller numbers, called the MSB number and the LSB number. The documentation for your MIDI device should specify what values to use here.

There are two independent NRPN Generators in this module, each is fully independent, but they do share one parameter (Data Rate). Each works by reading CV inputs, scaling or limiting that value to a range set with the Min Value and Max Value parameters, then generating MIDI NRPN messages from those values. The module keeps track of previously generated NRPN messages and only generates new ones when necessary.

The Scale Mode parameter determines how the CV input values are scaled to the target range for MIDI NRPN values (which is 1 to 16,383).

• If the Scale Mode is [-1, +1] then the input range is assume to be from -1.0 to +1.0, and those values will be scaled so that the output values will range from the Minimum and Maximum values specified by the Min Value and Max Value parameters.
  
  
• If the Scale Mode is [0, +1] then the input range is assume to be from 0.0 to +1.0, and those values will be scaled so that the output values will range from the Minimum and Maximum values specified by the Min Value and Max Value parameters.
  
  
• If the Scale Mode is "No Scaling", then the input range can be anything (but is mostly likely to be close to the MIDI NRPN range of 1 to 16,383). The input values will not be scaled, but passed through. In this case the Min Value and Max Value parameters are used merely to limit the range of values that are generated.

There is also a data rate parameter to limit the rate at which NRPN messages are generated from quickly-changing CV inputs. This parameter is very important when generating MIDI that will be directed to a hardware MIDI interface, as there is a hard limit on how many MIDI messages can be sent over a MIDI cable. If you are generating to a hardware MIDI device, set the Data rate to "L".

If you Mute one of the NRPN voices, that implies setting it to some default value. In this module, the base value is used as the mute value.

Parameters

Each of the two NRPN voices has the following parameters:

MSB Number
Sets the MSB controller number for generated NRPN messages.

LSB Number
Sets the MSB controller number for generated NRPN messages.

Min Value
Sets the minimum value generated NRPN values, in integer values from 0 to 16383.

Max Value
Sets the maximum value generated NRPN values, in integer values from 0 to 16383.

Scale Mode
Determines how CV input values are mapped to MIDI NRPN values. See the Overview section above for details.

MIDI Channel
MIDI output channel to use for generated NRPN messages.

(Data) Rate
This sets the maximum rate at which NRPN messages will be sent. The rates are:

• I (very high) -- no limit.
• H (high) 50 Hz -- every 20 ms.
• M (medium) 20 Hz -- every 50 ms.
• L (low) 10 Hz -- every 100 ms.

When generating NRPN messages to MIDI hardware ports, be sure to use the "L" range, as NRPN messages are generated as four MIDI CC messages (two for the NRPN number, two more for the value), so it doesn't take many NRPN messages to saturate a MIDI cable.

The MIDI transmission rate (over physical cables) is 31.25 Kbaud, which comes out to about 250 MIDI NRPN messages per second. If you are only sending MIDI messages to modules or software running on the same computer, high data rates should not be an issue.

Ports

The input port for generating NRPN values for the first "voice" of the module.

The input port for generating NRPN values for the second "voice" of the module.

All MIDI NRPN messages generated by the module are outputted through this port.