CTM64 (Contact To Midi Converter) Version 4 User's Guide © 2008 by Doepfer Musikelektronik
Electrical safety / EMC compatibility CTM64 is a so-called OEM product (OEM original equipment manufacturer) that cannot be used independently but has to be combined with additional electrical or electronical equipment to become a working device (e.g. keyboard, switches, buttons, potentiometers, power supply, case/housing). The manufacturer of CTM64 does not know the final assembly of the complete device in which the CTM64 is used as a part of the complete device.
Contents Electrical safety / EMC compatibility .........................................................................................................2 Warranty ...................................................................................................................................................2 Contents....................................................................................................................................................3 Introduction .............................
Introduction CTM64 is an universal MIDI Out kit. Up to 64 free contacts can be connected to generate MIDI note on/off or program change messages. CTM is suitable to retrofit keyboards, switch panels, button arrangements or any other contacts so that they are able to transmit MIDI data. Up to 4 potentiometers can be connected to generate common MIDI controllers, pitch bend and after touch. Additionally a 1/4 jack socket is available for connecting a sustain pedal.
We do not offer a suitable housing as the CTM64 is normally installed into the housing of the keyboard or switch board. An external power supply (7-12VDC@min. 250mA) is required. It is included with the CTM64 only within Germany. In other countries the external power supply has to be ordered additionally by the local dealer if necessary. We offer a suitable connector set for the CTM64 (25.00 Euro in Germany, i.e. about 30.00 US$).
Connections (11) common connector (JP6) (1) power supply 7-12V/ 100mA DC (BU3) (10) contact 49-64 (2) MIDI IN (BU1) (3) MIDI OUT (BU2) (4) control LED (D68) (12) jumper 1-8 (JP5) (10) contact 33-48 1 2 3 4 5 6 7 8 (10) contact 17-32 (10) contact 1-16 (5) sustain (BU4) (6) (7) (8) (9) potentiometer connectors for pitch bend, modulation, volume and after touch (ST1, ST2, ST3,ST4) page 6 +5V GND CTM64 Version 4 - User's Guide
Power supply (1) The CTM64 does not have a built-in power supply. Instead it uses a plug-in type external power supply (AC adapter). One reason for this feature is electrical safety. Keeping danger voltages (main) out of the CTM64 increases the electrical safety. Therefore an external power supply of high quality and safety should be used. If the keyboard is used in Germany the external power supply has to be VDE approved.
Potentiometer connectors (6,7,8,9) The four 3-pin connectors (6,7,8,9) are used to connect up to four potentiometers (rotary potentiometers, faders, wheels). The middle pin of each connector is the slider pin (or control voltage pin), the left one is GND, the right one is +5V. As the potentiometers are used as voltage dividers the resistance value of the potentiometer is not critical. Any value between about 5kOhm and 250kOhm will work without problems (linear response recommended).
Contact 1-64 (10) and Common (11) The 64 contacts are connected to four double row pin headers with 16 pins each. 16 pin socketconnectors (female) with flat cable can be connected to these pin headers (not included with the CTM64). Additionally there is one common pin (11) for all contacts. Pay attention that only free contacts can be used. This means that the contacts are not allowed to be connected with another electronics or connected with a fixed voltage (e.g. GND).
Operation CTM64 is switched ON by plugging the AC adapter into a wall outlet and connecting it to the appropriate jack (1) on CTM64 pc board. There is no separate ON/OFF switch. After power on the LED on the CTM64 will light up. Otherwise the AC adapter used is not suitable, has the wrong polarity or does not work.
Mode (jumper 5) Jumper 5 installed: Jumper 5 removed: note mode (factory setting) program change mode Note/program offset (jumper 8) Jumper 8 installed: Jumper 8 removed: offset = 0 (factory setting) offset=36 (in note mode), resp.
Check list In case that your CTM64 installation does not work at the first go please check the following points: • Is the power supply working correctly ? After power on the LED has to be on ! Otherwise the AC adapter used is not suitable, has the wrong polarity or does not work. The correct polarity is: outside ring = GND, inside lead = +7...12V.
Appendix: Connection sketch common lead for all contacts 64 49 48 33 32 17 16 1 +5V +5V +2.5V 16 pin female connectors with pressed 16 pin flat cable contact number GND GND potentiometer wiring for ST1 and ST2 potentiometer wiring for ST3 and ST4 resistor values for the potentiometers about 5k...
MTC64 The counterpart to CTM64 that converts 64 succeeding note messages into 64 0/+5V (TTL type) signals is called MTC64 (MIDI To Contact/Gate). With suitable drivers it is possible to control relays, lamps, electromagnets, electromagnetic valves, motors, dimmer packs or switch packs and so on via MIDI. The ideal control unit for the MTC64 is the CTM64. Closing a contact connected to CTM64 (e.g. buttons) leads to activate the corresponding element (e.g. lamp or electromagnet) via MTC64.
Additional jumpers for pcb version 4 For version of the CTM64 e few more jumpers are available. The sketch below shows the position of these additional jumpers. 64 note offset GND normal/toggle operation normal/inverted operation +5V The pin header JP7 is located near the LED between the MIDI out socket (BU2) and the foot switch socket (BU4).
Another pin header labelled JP8 is located right to the main processor. The jumper installed to JP8 has this meaning: Normal / Toggle operation • • Jumper installed in upper position (GND, towards the XTAL): Jumper installed in lower position (+5V) normal mode (factory setting) toggle mode When the toggle mode is selected the CTM64 transmits alternately note on and note off at each closing of the contact (opening the contact has no meaning in this mode). This can be used to realize a toggle switch e.g.
CTM64 Button Board and Front Panel As an addition to the CTM64 main board a button board with 64 momentary switches is available. The switches are arranged as an 8 x 8 matrix. The connection between the CTM64 main board and the button board is established by four 16-pin ribbon cables. In addition the common connector JP6 of the main board has to be wired to one of the corresponding pins of the button board (only one of the three pins of the button board is used for this).
Even a suitable front panel is available. The panel is punched matching to the 64 buttons and four mounting screws. The pc board is mounted to the front panel by means of four M2.5 counter-sunk screws, distance bolts and nuts. The measure of the front panel is compatible to the 19 inch standard: 3 U height (128,5 mm) and 20 HP width (101,3 mm). The front panel is not printed but labels with the numbers 1-64 and 65-128 are delivered. The front panel can be mounted e.g.
CTM64 Relay Board Another addition to the CTM64 main board is the CTM relay board. This boards contains 16 reed relays and allows the control of the CTM64 via a large distance (we tested up to 100 m). Up to four relay boards can be connected to one CTM64 main board. Simple 2-pole wires that have to be shortened at their ends (e.g. by momentary switches) are used to control the CTM64. For the CTM64 Relay Board a separate user's guide is available.
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