Doepfer R2M Midi-Ribbon-Controller - Manual (Page 4)

Page 4 R2M User's Guide V1.11
Introduction
R2M is a so-called ribbon controller that generates control signals by moving the
finger on the ribbon manual. The output signals are generated as Midi and CV/Gate
control voltages simultaneously. Consequently R2M allows to control both Midi and
CV/Gate based equipment (e.g. analog synthesizers or analog modular systems).
R2M is the abbreviation of Ribbon to Midi.
R2M is made of two parts: the manual and the control box.
The manual is made of a 50 cm long linear position sensor and a pressure
sensor that is located below the position sensor. Touching the sensor with the finger
generates a voltage that is proportional to the position of the finger. In principle the
position sensor works like a 50 cm long fader (i.e. slide potentiometer). The slider is
represented by the finger. As soon as the finger touches the position sensor the
slider contact is closed and the finger position represents the slider position. If the
finger is removed the slider is removed too (i.e. the slider contact open).
Additionally a pressure voltage is generated that increases with the pressure applied
to the position sensor. Both voltages are fed to the R2M control box via a four-pin
cable (same as USB but does not transmit USB data). For the manual the same type
as the for the modular version A-198 is used.
Fig. 1
The control box contains two analog-to-digital converters and a microcontroller. It
converts the data coming from the manual (finger position and pressure) into the
corresponding Midi data resp. CV/Gate voltages. The Midi input is used to transpose
the notes generated by the R2M or to control the R2M arpeggiator functions. The
programming of the device is carried out with a LC display, 10 buttons and 6 LEDs.
The control box is available even without manual to make use of an already existing
A-198 manual and take advantage of the additional features of the R2M control unit
compared to the comparatively simple A-198.
Remark: To detect if the finger touches the position sensor the slider contact is pulled
high if the finger is removed. This corresponds to the rightmost point of the position
sensor. This has no influence on to the general operation of R2M but the last few
millimeters at the right rim of the manual cannot be used – i.e. moving the finger
within a few millimeters in the rightmost position has no effect.