I recently purchase an upstream amp and found there an UART interface (RX/TX pins). Looking at this topic i found that the UART sends all needed information for a status & title display.
Then i assembled an ATTINY3216 together with a SSD1309 driven OLED display and connected this to the upstream UART interface. After severals days of coding i got this:
and for audio sources with title information:
To get a visual response when using the remote i added pop-up screens showing the current value being changed:
I’ve now created a GitHub repository with the microcontroller source code:
Feel free to use this for your own projects!