PS2MIDI - 5 Dollar MIDI Keyboard using a PS2 Keyboard and Arduino

for an arduino project, it is very!!! simple to build - basically, you only need one resistor and the midi cable

I posted this some years ago on instructables .com

• but also wanted the project to be here -

if you want to build this thing, go there to download the Arduino Code, Libraries etc.
since i dont know how to upload .zip files here...
http://www.instructables.com/id/ps2midi/

ps2midiVERSION2 by sir triggalot

sorry for the typo layout ;)
just load the zip file - includes library, ardu file, manual

ps2midi is an application for a ps2 computer keyboard,
to be used as standalone midikeyboard. it is based on arduino.
It has features that normal midikeyboards DON ́T HAVE :)
it ́s simple, cheap, available and inspirational.

It has chromatic pitchbend !!! (intresting esp. for using with mpc in combination with jjos)
pitchbend range is divided in 12 steps up (semitones) and 12 steps down (semitones)
if pitchbend range of used instrument is +/- 12 , you can play the instrument "by pitchbend"

features:

-Full MIDI Note Range
2 octaves keyrange - 10 octaves all together (note #1 - note # 127) octaves are chosen with keys F1 - F10

"SPECIAL KEYS" =>
"DELETE", "RETURN", "rightSHIFT", and "SPACE" used to play up to 4 midi notes simultaniously
very cool for chords or drumz ;)

by default, "DELETE", "RETURN", "rightSHIFT", and "SPACE" play these notes: "C+++", "C++","C+" and "C"

Concept of "SPECIAL KEYS" :
keep in mind !!! :
every time you push a "NOTE KEY", the last stroke is remembered.

Every SPECIAL KEY has 4 Layernotes to play, defined by the

"LAYERKEYS" =
"T AB"(Layer4), "Capslock"(Layer3), "leftSHIFT"(Layer2), "CTRL" (Layer1)

By default, only one layer(LAYER1) ist loaded. How to load a NOTE into a LAYER:
First Push a SPECIAL KEY to choose SPECIAL KEY then

Push a LAYERKEY together with the desired SPECIAL KEY and the last remembered NOTE is loaded.

-to Silent a LAYER:
push the LAYERKEY together with key "Q"

-Listen to a LAYERKEY:
Just Press the Key

concept of layering:

LAYER 1 is dominant.
Always stack up from LAYER 1
if you choose the same notes for other layers; they wont play !

=> to empty a SPECIAL KEY, you can quickly choose 4x times the same note for each layer => only this note is played once by layer one

"Q" KEY does the same thing, it makes the layer the same note as layer 1, so it wont play.

in pitchbend mode - dont choose Layernotes accidently by pressing Layerkeys and Specialkeys together.

• Velocity +/- / Full On / Accent

key: "^" and "1" change velocity of keystrokes -/+
key: "2" (accent): if pressed and hold, velocity is 127

Single Layer Velocity:

Cursor UP / DOWN change actual LAYER Velocity
Cursor LEFT / RIGHT change actual SPECIALKEY Velocity all togehter
to RESET LAYER Velocity: => press Arrow "LEFT" and "ESC" togehter.

All Notes Off

If it gets too messy => push "ESC" for ALL NOTES OFF* *works with mpc... - in vst world... often doesnt work...;(

3 Different Modes:
Modes can be changed with key "F12" - keyboard lights show witch mode is on. SPECIAL KEYS work in every mode.

1-PIANO Mode:

"scroll" light is on.
In normal mode the "note"keys play midi notes.
"NOTE KEYS" are:
z,s,x,d,c,v,g,b,h,n,j,m," and "e,4,r,5,t,y,7,u,8,i,9,o,p" octaves are chosen with keys F1 - F10

2- Chromatic Pitchbend Mode:

"scroll" and "caps" lights are on.
NOTE KEYS are PITCHBEND KEYS.
pitchbend range is divided in 12 steps up (semitones) and 12 steps down (semitones)
if pitchbend range of used instrument is +/- 12 , you can play the instrument "by pitchbend" very !!!!! cool with mpc (jjos) and chopped samples !!!!!!!!!!

SPECIAL KEYS are tweaked too.

3-MPC Mode:

"caps" lights are on.
similar to mode 1 -but !!!
key notes are like mpc drumprogramm notes only "white" keys are used - to refer to the drumpads, lower octave is pad 1 - 8 upper octave is pad 9 - 16 key "F1 - F2 - F3 - F4" is bank A - B - C - D

"DRONE":
key"F11"
if you hold "F11" while releasing aNOTEKEY orSPECIALKEY => no "note off " is sent.
=> the note is on hold

little video to get an idea of the project:

ps2midi tutorial from Sir Triggalot on Vimeo.