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Frequently Asked Questions.
MIDI & Music
MIDI and Music Information
MIDI Realtime Filter


MIDI Realtime Filter


The MIDI Realtime Filter can be used to block MIDI Channel messages (eg Program Change etc) but allows MIDI Realtime messages (eg MIDI Time Code (MTC), Start, Stop, Continue and Timing Clock messages) to pass.






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MIDI Realtime Filter


PRICE:  €50.00







The MIDI Realtime  Filter unit utilizes:

  • An assembled, built and tested MIDI Boarduino including a suitable pre-programmed Atmega168,
  • A 2.1mm power socket, and associated LED, 
  • A MIDI detection LED,
  • A 150mm wired MIDI 5-pin DIN input socket,
  • A 150mm wired MIDI 5-pin DIN output socket, 
  • The circuit schematic is available,.



The MIDI Realtime Filter  requires:

  • A 9 Volt battery or equivalent 9 Volt DC external power source, .




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The MIDI IN and OUT connectors use  5-Pin 180 degree DIN sockets. Note that the MIDI IN/OUT wiring is polarised and the correct pins should be used.







The unit detects the incoming MIDI data and if it is MIDI channel data then the MIDI message is blocked and prevented form passing through.


However if the  MIDI data is not MIDI channel data, but MIDI Realtime data, then the data is passed through to the MIDI out socket.


MIDI Specification: 

The different MIDI message data information is available.



midi_boarduino_PINS_wiring.jpg (191151 bytes)



Power Supply:

The MIDI Boarduino can be powered via the USB connection or with an external power supply. The power source is selected by the PWR_SEL jumper. To power the board from the USB connection, place it on the two pins closest to the USB connector, for an external power supply, the two pins closest to the external power jack.


External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector. A low dropout regulator provides improved energy efficiency.


The board can operate on an external supply of 7 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.