Oxygen Series
User Guide
6
16,384 step resolution through combined Coarse and Fine messages
Most assignable MIDI controls, including those on your Oxygen series keyboard, operate with a resolution of 128
steps. Standard MIDI CC messages that can be used universally between different MIDI devices are also limited to
a resolution of 128 steps. However, the RPN/NRPN concept allows for a resolution of 16,384 steps by combining
two 7-bit MIDI messages into a 14-bit message ( fine).
Hardware controller knobs or sliders that take advantage of the full 14-bit RPN/NRPN resolution are very
uncommon. To illustrate the concept and make the purpose of RPN/NRPN Coarse and Fine messages easier to
understand, we included a graphic describing how such a 14-bit RPN/NRPN control would operate (not supported
by Oxygen Series keyboards):
The RPN/NRPN coarse message divides the range of 16384 steps into 128 segments and activates them by
sending each segment's first value, while the RPN/NRPN fine message provides the 128 steps of resolution
contained in each of these segments.
Coarse
9
8
7
6
5
4
3
2
1
0
16,384
127
9
8
7
6
5
4
3
2
1
0
127
9
8
7
6
5
4
3
2
1
0
127
3
9
8
7
6
6
5
5
5
5
4
4
4
4
3
3
3
9
8
7
6
6
5
5
5
5
4
4
4
4
3
3
9
8
7
6
6
5
5
5
5
4
4
4
4
3
3
1
2
0
Fine
Fine
Fine
16,384
0
