My ideas for this design:
* Minimum site (currently 100x70mm)
* servo can be supplied with seperate power
* pinout for each connection
Problems that maybe occur:
* interference between pwm and adc
* interference between pwm and pusbutton
* spi select slave maybe not on the apropriate spi channel
* right caps used ??? (low esr), how much µF shoud i use ???
Currently it doesn't fit completely under the discovery board, hold your discovery board on the screen to see what i mean.
I can order a batch at seeedstudio(costs 3€+shipping for one pcb), but this will be organized later !!!, currently I'm only searching for improvement capabilities.
Maybe i can also order some components at mouser and sell a complete diy solder or already soldered kit for prime cost + donation ;)