Arduino nano

[gabsummer]

hi Man, can you give me more information?
i can use your sketch with an arduino nano?
The library DIO2.h runs on ATmega328P?
Do I have to insert pull up resistors? can I do without it or do you advise me to insert them, if yes, would you tell me how?
When everything is ready, do i need to use programs like loopMidi and Hairless-midi or is it ready like this?
Thanks in advance and forgive me for my not perfect english :)

[oxesoft]

It depends on how many keys you keyboard have. For using Arduino Nano you probably must use some multiplexers ICs, because it hasn't enough pins to directly connect your keyboard. In case of you have an Arduino with enough pins do direcly connect your keyboard there is also internall pull up resistors, activated by software. Please see more details here