To interface Volumio on Raspberry pi in a DAC who controled by a controler (LCD + buttons on it, on the existing matérial), we must establish a communication with the 2 controlers together if we want interface Volumio rasberry Pi with other controller : to create for exemple the absolue Network player .
It would be great to create a communication with the serial port (RS232) or SPI port for the information on the played track (for exemple, to use on the screen on the other controller).
It would be great to use GPIO to connect for exemple an input to control the shutdown of the raspbery pi or to wake up it.
It will be great too to choose GPIO inputs via interface to enable controle actions like : the next / Back track, pause, play and other simples actions, driver by other controler or by buttons directly.
One GPIO (output) could be enable when a track begin for the first time since the start up of volumio : to enable ampli, lcd or something else.
It will be great to implement an automatic of the raspberry pi of volumio stop with delay.
It will be great too find the same hardware controles via GPIO with the SPI or Serial (RS232) interface with simple instructions to communicate (ask <-> answer) and be very open with other hardware controlers for the DIY world and accelerate the distribution of Volumio like THE solution of the dematerialized music .
Restart MPD with a control via serial interface or GPIO will be great.
Or with the volumio parameter GUI interface, determine an action / GPIO Input and a status / GPIO output will be be an excellent solution of customization of volumio ! A lot of possibilities will be open with that !!
I’ve find this library for exemple and the controle ’ (get-status CONN) ’ or ’ (get-stat CONN) ', that can communicate importante information about the track. : wiki.call-cc.org/eggref/4/mpd-client
This evolution is very important i think to develop volumio on DIY world to interface with no PB with others Hardware solutions.
I can developp my ask if you want more detail .
At your disposal