MIDI Channel Filter

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Description:

The MIDI Channel Filter can be used to reduce MIDI throughput by removing MIDI System mesages. Also it allows one channel to operate a particular sound module/synthesiser, while filtering out the other MIDI channel data. Note that this unit operates via the MIDI IN and OUT sockets only and not through the USB connection.

Operation:

The unit detects the incoming MIDI data and if it is a MIDI channel command, which corresponds to the DIP switch MIDI channel (1-16) setting, the device will pass only data on that selected channel and discard data on all other channels.

If any System Common, Realtime or Exclusive events are detected they are passed directly from the input to the output. System Exclusive messages will be sent until the End of System Exclusive message is received. However if a system realtime message is received during a System Exclusive message it is also passed to the output.

Power Supply:

External power can come either from an AC-to-DC adapter or battery. The adapter can be connected by plugging a 2.1mm center-positive plug  into the board's power jack.

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.

MIDI Channel Selection:

The MIDI Channel Filter commands are all channel (1-16) dependent. The system will also work with MIDI running status.

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Features:

The MIDI Channel Filter Unit consists of:

• An assembled, built and tested Arduino board including a suitable pre-programmed microcontroller,
• The MIDI channel (1-16) is user selectable via the 4-way DIP switch
• A 2.1mm power socket, and associated LED,
• A MIDI activity LED,
• An assembled, built and tested MIDI In/Out Board,
• A 150mm wired MIDI 5-pin DIN input socket,
• A 150mm wired MIDI 5-pin DIN output socket,

The MIDI Channel Filter Unit requires:

• a 9v battery or equivalent DC power source

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Resources:

The MIDI Channel Filter Unit Resources:

• The MIDI IN/OUT circuit schematic is available,
• The MIDI IN/OUT wiring is also available.
• The Arduino Uno Board Schematic is available,
• The Arduino Uno Board Pin Layout is also available,
• MIDI Source Code for the Arduino.

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