Context: I designed and successfully deployed a custom Android Auto head unit in my car at 17. After a week of messing about with the code and learning a bit about Debian and it's properties, my phone connects flawlessly to my head unit with audio and display.
Issue: Raspberry Pi SBCs were and are not designed to provide a significant enough current from the USB ports to charge most flagship phones, I have a Pixel 9 Pro XL. While connected to the head unit, my phone draws more power than the USB ports on the Pi can handle (shared 5v@~1.1a), which in turn does drain the battery on my phone rather than charge it.
I have bought a USB C splitter which in theory should allow the phone to both charge off of a separate device as well as provide a connection to the Pi. This does not work. I can only use this to charge the phone and it refuses to allow connection to the Pi. Now, something I did to eliminate boot times on the Pi was connecting it to the battery of the car with a low voltage disconnect, and connect the screen to a separate circuit that only comes on when the key in the car is on. The data transfer pins for the touch screen are connected separately to the Pi through another cable and this works when there is voltage applied from the other cable to power the screen.
My question to you is, would removing the 5v power on the USB cable from the Pi to the USB splitter allow me to charge the phone from a separate adapter, and transfer data to the Pi? If not, is there a different USB adapter I could purchase to make this happen? I know PD/PPS requires the use of data pins so I am open to anything. Not as easy as just tying in the data wires with the power wires like I did on the screen.
Issue: Raspberry Pi SBCs were and are not designed to provide a significant enough current from the USB ports to charge most flagship phones, I have a Pixel 9 Pro XL. While connected to the head unit, my phone draws more power than the USB ports on the Pi can handle (shared 5v@~1.1a), which in turn does drain the battery on my phone rather than charge it.
I have bought a USB C splitter which in theory should allow the phone to both charge off of a separate device as well as provide a connection to the Pi. This does not work. I can only use this to charge the phone and it refuses to allow connection to the Pi. Now, something I did to eliminate boot times on the Pi was connecting it to the battery of the car with a low voltage disconnect, and connect the screen to a separate circuit that only comes on when the key in the car is on. The data transfer pins for the touch screen are connected separately to the Pi through another cable and this works when there is voltage applied from the other cable to power the screen.
My question to you is, would removing the 5v power on the USB cable from the Pi to the USB splitter allow me to charge the phone from a separate adapter, and transfer data to the Pi? If not, is there a different USB adapter I could purchase to make this happen? I know PD/PPS requires the use of data pins so I am open to anything. Not as easy as just tying in the data wires with the power wires like I did on the screen.
Statistics: Posted by POPC47 — Tue Oct 01, 2024 5:49 pm