MIDI 16_Way Light Controller

A Miduino kit including a suitable pre-programmed Atmega168,

A 2.1mm power socket, and associated LED,

Select MIDI channel at power-on, in programme mode,

Select MIDI start-note at power-on, in programme mode,

A MIDI 5-pin DIN input socket,

A MIDI 5-pin DIN output socket,

16 off 0.1" pin-terminal outputs,

Outputs (0-15) are programmable from first MIDI note on/off command,

The circuit schematic is available,

A programme mode switch and associated LED

The MIDI 16-Way Light Controller also requires:

A 9v battery or equivalent DC power source

Suitable interface circuitry

Assembly:

The assembly is straightforward and well documented. This design does not include a USB chip, it is designed to use a FTDI USB 232-TTL cable to program the microcontroller. However since the cable plugs directly into the Miduino, you can use one cable for multiple projects.

MIDI Wiring:

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.

Normal Mode:

The unit detects the incoming MIDI data and if the MIDI channel corresponds to the correct MIDI channel setting, when a corresponding Note-on is detected, (to the pre-set note-on data), the corresponding output is switched on (+5 Volts) and stays on until the corresponding note-off is detected and the output is switched off (0 Volts). This allows each output to operate independently.

Programme Mode:

At power-up, when switching on the unit, if the programme switch is pressed and held on, then the unit will enter programme mode, and the programme LED is lit.

Now the first Note-on command from a MIDI keyboard or sequencer is detected and stored in the EEPROM. This note is the first of 16 consecutive note values, associated with outputs 1 to 16. Also the MIDI channel, which the Note-On command is transmitted on, is also stored in the EEPROM.

After the Note-on is detected the unit goes into normal operating mode, and the programme LED is off. So the 16 outputs are programmed to operate consecutively from only the first Note-on command detected.

Programming the unit only has to be done once and the MIDI start-note and channel are stored internally in the EEPROM and the unit will continue to operate in this mode, (even when power is removed and re-applied), until the unit is re-programmed.

Purpose:

The MIDI to 16 outputs unit can be operated live in real time from a MIDI keyboard or from a hardware/software sequencer with pre-programmed MIDI Note on/off data. The outputs can be used, via suitable interface circuitry, to switch electrical devices, such as lights, motors, pumps etc., in time with the music. Use the outputs to control and synchronize auxiliary circuitry. This provides a direct interface to the world of analogue electronics.

MIDI Specification:

The outputs are switched ON via MIDI 'Note-On' commands and OFF by MIDI 'Note-off' commands. These MIDI commands are all channel (1-16) dependent. Also, the outputs will switch off if a correct MIDI Note On with a velocity of 00 is received. The unit also works in MIDI Running Status mode.

Expansion:

The MIDI to 16 output units can be combined/expanded by connecting the MIDI OUT of one unit to the MIDI IN of the following unit. Thus producing 16, 32, 48. etc. outputs.