rework of simple analog arpeggio to run on nano and with an external can 16bits ADS1115
typicaly the purpose was to add an arpeggiator to my korg MS10.
-vcoOut: pin9 (PWM16bits) -pwmLed: pin10 -gateIn: pin8 -gateOut: pin11 par defaut(modifiable)
-buttons&switch pin 3-7 --sw: START HOLD PATTERN ; --push but: RESET(connect on START sw) UNDO,BLANK,REPEAT
-tap push butt: pin 2 because we need int0 USE BY arp class
-duration rotary: adc6 pinA6 -mode rotary: adc7 pinA7