Hello,... I have a USB host shield, and Arduino UNO (or Mega 2560 if preferred) and a Olimex Midi Shield. I only need to send note on/note off commands for 13 notes (C to C) using the following keys:
Q, 2, W, 3, E, R, 5, T, 6, Y, 7, U, I corresponding to:
C Db D Eb E F Gb G Ab A Bb B C (in a low octave range, but I assume I can make changes if need be).
One thing to be aware of... if you hold down a typing key, a standard USB keyboard is designed to fire the key multiple times before you lift your finger (sending a note off message). This will need to be eliminated so that the USB keyboard sends note on/note off.
For any that might recognize this subject,... I had received info on how to possibly make this happen on another forum,... and I eventually make a converter to make it work using 3 Arduinos (I know, ridiculous). It worked great,... but to test I was using a generic WalMart USB keyboard... and I actually eventually needed this to work with an HP SK2885 (long story)... but didn't have one to test with until today and it doesn't work with it. I think the reason is that I was using a PS2 library and I think the WalMart special had some kind of cross protocol compatibility (I have read about such things).
Anyhow,... I'm out of time and out of patience. I should have used a USB shield to begin with.... but I found a music project with a PS2 based project code that that I monkeyd around with and got it to accept the usb keyboard I had.
I will pay $40... it's just gotta work (that's the only criteria :)
Thank you for your consideration... Jim