MC-1 - MIDI-Clock Generator for VMC


MC-1 is a software to run on the VMC-system. It provides a MIDI Clock generator. 

For the Installation please use the ARDUINO IDE, see An introduction how to upload the program with the Arduino IDE can be found here.

The software is published as open source under the creative commons license 'by-nc-sa 4.0'

MC-1 - Users Manual

Firmware Version 1.2
VMC-1 Hardware Version 1.5.4

'MC-1' is a programm for an Arduino Nano mounted on a “fanwander VMC-1'. The programm generates MIDI-Clock in variable tempo from 20 BPM to 275 BPM. The tempo can be changed either continously or can be preset and the change is invoked by a button press.
MIDI Start and MIDI Stop commands are sent either by buttons or by incoming triggers. The MIDI-Clock continues running even if the status is STOP

Since version 1.2 it is possible to edit the settings of a fanwander Clock Boy module.

If your VMC-1 runs a different software at the moment, then please consult the programming instructions for the VMC-1 on how to install software.


...for those, who think they don't need manuals:
  • The function of the five buttons

    Stop Mode PLAY
    realtime tempo change
    send tempo change -10 tempo +10
    tempo -1 tempo +1
    Play Mode
    STOP realtime tempo change
    send tempo change -10 tempo +10
    tempo -1 tempo +1

    Setup Mode (* see below)
    Select Param
    Exit Setup
    < Parameter >
    Set Param

    -- Value ++

    Clock Boy Editing
    toggle between normal mode and Clock Boy mode
    Edit Clock Boy

    transfer value to Clock Boy
    CV1 = select parameter
    CV1 = select value
    (*) at the moment there is no parameter to setup, so there is no setup-menu
  • Good Luck :-)
Now more details for the patient ones...

Connect and Configure the Hardware

This is described in the users manual of the VMC-1.

MIDI connections

Basically you need only a device which receives MIDI-Sync (I will call this 'the sequencer'). I will not explain how to connect MIDI devices. So establish the following MIDI connections

VMC-1-MIDI-Out <-> Sequencer-MIDI-In.

At the moment there is no setup function. The software runs as it is.

You have to setup your "sequencer" (or what ever you want to control by the MC-1) to receive MIDI-Clock and MIDI-Start/Stop commands. Since this depends completely on your device I cannot provide detailled help. Usualy this is called like "external clock".

Generic Function

On power up the display will report its version and then it will look like this:

STOP current=120
pot=192 btn=119

The display shows:
  • upper row left: the status 'PLAY' or 'STOP'
  • upper row right: the tempo currently sent out.
  • lower row left: the value provided by the tempo-knob
  • lower row right: the value provided by the buttons F1/F2

The LED aside the TEMPO knob will blink on quarter beats of the actual sent tempo.

Setting the Tempo

There are two modes to set the tempo: the preset mode and the real time mode.

For the preset mode you do either:
  • Set the tempo using the buttons F1 (=decrease) and F2 (=increase). Pressing only one button changes the tempo for 1 BPM. If you press and hold one button and press then the other button, the tempo will change for 10 BPM. => The value btn=... will change accordingly.
  • Now press WRITE. => The currently sent tempo will jump to this value
  • Set the tempo using the TEMPO knob. => The value pot=... will change accordingly.
  • Now press and hold WRITE and then press F1. => The currently sent tempo will jump to this value.

For the real time mode press and hold both WRITE and F1 and set the tempo with the TEMPO knob. To avoid unwanted jumps in the tempo change, you should set first the TEMPO knob to the value that is displayed as "current" and do the real time change then.


To send a MIDI-Start-command press the play button.


To send a MIDI-Stop command press the stop button.
Remark: this will send only the stop command. The clock will continue running. This is recommended by the MIDI specification, and is urgently required for many devices.

Setup Mode

At the Moment there is no setup menu

Clock Boy Edit Mode

Beginning with version 1.2 MC-1 can control the parameters of the Clock Boy modul, similar to the Clock Man module. To switch to this mode simply press F1 and F2 together.
Now the CV1 potentiometer will select the parameter to be controlled. The CV2 potentiometer will select the value for this parameter. (ATTENTION: do not plug cables into the sockets for CV-1 and CV-2 when using the MC-1 for Clock Boy editing!)
Pressing the WRITE button transfers the value for the selected parameter to the Clock Boy.
The last parameter (CV1 turned fully clockwise) is the selection of the MIDI channel on which the MC-1 sends the data to the Clock Boy. Available MIDI Channels are 1 to 6 (on the Clock Boy only six different channels can be selected).

The MC-1 sends those data as ControlChange messages #70 - #75.

All product names and brand names beside “VMC-1”, “ChordTrigger”, “Clock Boy”, “Clock Man” and “fanwander” belong to the corresponding owners. They are mentioned only for educational purposes.

All rights reserved, by Florian Anwander 2020 - 2023