MIDI Channel Filter

The MIDI Channel Filter unit utilizes:

• A Printed Circuit Board (PCB), 
• A pre-programmed 16F877 PIC,
• A PCB screw terminal power socket  and associated LED, and 9v battery connector
• A 4-way DIP switch which selects the MIDI channel at power-on, shown in table 1
• A MIDI 5-pin DIN input socket,
• A MIDI 5-pin DIN output socket,
• The circuit schematic is available in GIF format,
• The circuit layout is also available.

The MIDI Channel Filter  requires:

• A 9 Volt battery or equivalent 9 Volt DC power source

Operation:

The unit detects the incoming MIDI data and if the MIDI channel corresponds to the DIP switch MIDI channel setting, when a corresponding MIDI channel event  is detected, then the MIDI data is transferred to the MIDI output.

However if MIDI data from another MIDI channel is detected it is filtered out and it is not transferred to the output.

Also any non-channel events are filtered out. So any System Common, Realtime or Exclusive events are ignored.

Purpose:

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.

MIDI Specification: 

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