the advanced midi interface for the littlebits synth kit


[1] usb socket

connect to a computer, to transfer midi data in and out via usb, or use a usb power adapter to power your MIDIbit without being tied to a computer. midi messages received here will be translated into control voltages at the [9, 10] ouputs. they are also output on the [4] midi out connector.

[2] midi in, [3] midi thru and [4] midi out sockets

connect your midi keyboards, sequencers and other hardware. midi messages received at the [2] midi in socket are translated into control voltages at the [9, 10] outputs. They are also output via the [3] midi thru and [1] usb connectors.

[5] 5V buck/boost regulator

since all of our synthesiser modules are voltage controlled, this really is essential. it will maintain things like oscillator tuning and control voltage range even if you use a poor quality power supply.

[6, 7] programming jumper and reset button

closing the jumper and operating the reset puts the MIDIbit in programming mode, where it shows up as a usb flash drive, allowing you to update the firmware.

[8] expansion sockets

several expansion sockets, for future input/output expansion boards, ensure that you’ll never outgrow the capabilities of your MIDIbit.

[9] analogue outputs

the MIDIbit is equipped with three analogue outputs. as standard, they are pre-set as note, velocity and mod wheel and will respond to midi messages on midi channel 1. its possible to independently customise both the midi channel and the midi message of each output. amongst many other combinations, this allows us to set up to three part polyphony.

[10] digital outputs

the MIDIbit has two digital outputs, gate and clock
the gate output switches on when a midi note is received and stays on until a the note is released. use this to trigger littlebits modules whenever a note is played. the gate midi channel is user definable the clock output responds to midi sync messages, giving a pulse every 1/16th of a bar. this resolution can be set anywhere between 1/64th and 2bar. clock pulses can also be swung to enable groove effects.

[11] analogue inputs

the three analogue inputs are note, velocity and mod wheel. note and velocity work with the gate, digital input, to build a midi 'note on' message. when the gate input is triggered, the note and velocity inputs are sampled, converted to midi values and output as a midi note on message via [1] usb, and [4] midi out.
the mod wheel input is used to create a midi cc (continuous controller) message. it is continually sampled, generating a midi cc message, via [1] usb, and [4] midi out, whenever input changes.

[12] digital inputs

the gate input is used in conjunction with the note and velocity inputs, as described above. the clock will translate a pulse train into a midi tempo. the frequency of the pulse train will determine tempo, with each pulse generating a midi clock message each 1/16th bar.