So my last project where I was going to convert a TASCAM CD Player into a Volumio Streamer was a bust, so now I have had to look at alternate plans for this one, I seem to be on the right track, BUT, there is something I am confused about and I need someone’s help, so here goes:
So I have 3 items that I need to add to my build:
Hifiberry Digi2 PRO
Power Management Board
Rotary Encoder
All using the GPIO Pins.
Now I heard of the GPIO Expander, but it needs to have a certain chip (MCP23017), is there anywhere I can find a board that is already made and assembled?
What kind of power management board do you plan to use ?
The Hifiberry Digi2 Pro will not use all GPIO pins, have a look at the Hifiberry site.
So usually there should stay some GPIOs free for use with the rotary encoder.
There are ready MCP23017 boards, but you will require additional code to use them.
So I checked on Hi-fi berry’s website, and I saw the below:
HIFIBERRY DAC+, DAC+ ADC, DIGI+ AND AMP+, DAC2 PRO
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.
On the HiFiBerry Digi+ Pro GPIOs 5 and 6 are also used and cannot be used for anything else.
And the board for power management uses the attached.
Using the Digi2 Pro will not be possible with that power board out of the box - both use GPIO5.
With a little tinkering the software of the power board could be altered to use eg. GPIO6 but you would also have to do a little hardware tinkering to connect the board to GPIO6 - not possible without a little soldering.
What type of Raspberry PI do you plan to use ?
If you’d use a PI3b (not the Plus one !) you could use a more simple power board without cooling.
😵💫
