10-05-2024, 08:58 PM
(01-17-2023, 06:13 AM)pinus_pinea Wrote: I had another thought: is it possible to create some kind of add-on board/card using the PCIe x4 connection, some kind of bridge chip, and possibly some kind of MCU or other supporting ICs, that one could install through the M.2 connection, and then create a port physically somewhere on the case (I'm actually thinking of somehow machining the aluminum bottom case somehow to do this but whole other can of worms)? A whole "GPIO board" mounted on that connection using that bus?
Yes, it's possible. PCIe/UART bridges exist, but I suggest starting with an internal USB hub and a USB to UART bridge. I'd recommend modifying the below project to hold a USB/UART bridge, then manually running the USB connection from the test points on the board. I'm not an EE, but I believe you should be able to drop the UART bridge project's component set into the PBP WiFi project in KiCad. Then, with some layout and routing, you should be good to go
https://github.com/TobleMiner/PBP-NGFF-A-E-adapter
https://github.com/jiegec/HT42B534USB2UART (any other project like this should work but this one is just what i plucked off google)
