HiFiBerry DAC+, Digi+ and Amp+
GPIO2-3 (pins 3 and 5) are used by our products for configuration. If you are experienced with I2C, you might add other slave devices. If you a a novice, we don’t recommend this at all.
GPIOs 18-21 (pins 12, 35, 38 and 40) are used for the sound interface. You can’t use them for any other purpose.
On the HiFiBerry Digi+, GPIO16 is also reserved.
I plan to use external power supply for Dac+ Sandard / Pro / Digi+ without remove R14. So i have some question:
- Pin Ground on RPi2 / RPi3 may need to connect to Dac?
- Pin 3.3V may need to connect to Dac?
Thank you very much!