Photo of the setup. On the left side a PCIe switch card with one uplink port going through USB3 cable. It's upside down and 2 resistors are hacked on the PET PCIe lanes to foot RX detection. On the top right, the RPI5 with PCIe hat and my board plugged in it with a SFP module and optical cable coming out. On the bottom right another one of my board with SFP module and optical cable coming in. That one it plugged into a PCIe slot going through USB3 cable, going to the PCIe switch board.
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