Messages

This helps enormously, thanks. I don't know the MCP3208 ADC. I planned to:
- remove the RGB LEDs, that frees up pins D5, D6, D9, D10 and D11, and remove the switch, that frees pin D2
- add a multiplexer 74HC4051 which takes 3 digital pins and one analog pin (A3), then 8 pots go to the multiplexer and 3 stay on A0,A1,A2
- A4, A5 are ready to act as SDA and SCL to connect to the LCD 1602 board

That leaves me with 3 free digital pins for further expansion.

That seems easy. 
Now the software - not so easy 

Thanks very much Paul! For the update of the libraries (dind't try it yet) and for the diagrams. At least I found a new folder in github called "docs" which contains an html that opens a lot of info on the classes, files and interaction. This looks very complex for a beginning programmer.. 
I thought of the following customizations:
a. add a single din midi in (thru optocoupler)
b. add five pots so you dont need the switch
c. I will need a multiplexer for freeing up digital (a) and analog pins (b)

And if and when I succeed in all that I would like to try to add a 2x16 I2C lcd screen, to replace the 2 multicoloured leds.

I am going to study your diagrams.
Any hints where to start are off course very welcome

Have you made any progress customizing the arduino code? I succeeded in getting the miniAtmegatron working on my Arduino nano with v2.6 of the libraries (thank you Paul!). But as an Arduino beginner I don't have a clue where to start. I am used to the structure of .ino files. But the .ino file for the miniAtmegatron is almost empty, so everything appears to be happening in the libraries. But which library do I start with? Min? Or MinEngine? I understand the function of libraries for subroutines like behaviour of pots of oscillators. But where is the main program flow hiding?
Would be glad to hear some clues on this.