Problem is, this is my first ever electronics project beyond grabbing a WeMos D1 Mini and slapping WLED on it via a website. So I've spent the past month or so reading, and learning, teaching myself electronics design, ripping apart other designs, and how to use KiCad.
High level overview is this is basically a door access controller. The P4 was chosen due to wanting Bluetooth, Wifi, & Ethernet connectivity with the ability to handle multiple USB Camera streams. Ultimately I want to have App control, with the ability to tie into voice assistants(Alexa, Siri, etc.), and home automation software.
As for the board:
There is a circuit that detects if the door is open or not, another to activate a solenoid, and of course a USB-A connector for a camera.
Power can be provided via an external 48V power supply, or if the Ethernet Module is installed it can be powered off POE++.
The board has 3x 4 pin heads that goto seperate DC-DC Buck Converter cards that take the 48v and create the needed +3.3v, +5v, and Solenoid voltage (+12v-36v).
The DSI has been exposed as 2 Lane to a 22 Pin FPC Connector for a local display.
There is an RJ45 connector onboard that is used to connect to a daughter board that expands the number of doors, solenoids, and cameras. The RJ45 passes the +48VDC, the I2C Bus, and the USB Hub's Channel 2. Current design allows for upto 4 Daughterboards in a Daisy-Chain. I don't expect the max run from the main controller to the first daughter board to be over 2m, and possible 10m to the very last one. All daughter boards have a P82B715 on the inbound side of the I2C bus, and their own 4 Channel USB Hub.
For the I2C bus I went with Potentiometers as the pullups in series with a 220ohm resistor. My reasoning for this is that I won't know the end configuration and pots allow some form of tweaking while the 220's give an absolute floor.
I've tried to expose every pin the ESP32-P4 module has for future use, with the exception of the CSI, as due to the distance limitation on that I decided it wasn't work the hassel.
I plan on using the IDC Antenna connector and not the internal antenna.
So, because this was cobbled together from many different datasheets, and schematics, and I don't fully 100% understand (yet) how some of this stuff works, or why certain things were chosen. I'm hoping you all will be willing to help me and just give it a once over to see if there is anything I did wrong, should change, or ways to improve the design.
I've attached the PNG & PDF versions of the schematic, and also, I have rough draft of the PCB done as well.. Tho it's an older revision that dosen't reflect some changes I've made so far.