How to use pci express serial card in raspberry pi compute module 4?

Pineboards adds four more Raspberry Pi 5 PCIe HAT+ boards with raspberry pi 4 pcie slot Compatible with Raspberry Pi 5B · PCIe FFC connector to standard PCIe x4 slot, enabling compatibility with a wide range of PCIe expansion cards raspberry pi slot machine Raspberry Pi PCI Express device compatibility database The Raspberry Pi has PCI Express! There are some quirks to getting certain devices working with 64-bit

raspberry pi pcie slot PCIe cards, which might include NVMe, SATA, networking, or USB The major user connectors are located along one side to make enclosures simple Compute Module 4