126.96.36.199. Avalon-ST Packets to PCI Express TLPs
The following figures illustrate the mappings between Avalon-ST packets and PCI Express TLPs. These mappings apply to all types of TLPs, including posted, non‑posted, and completion TLPs. Message TLPs use the mappings shown for four dword headers. TLP data is always address-aligned on the Avalon-ST interface whether or not the lower dwords of the header contains a valid address, as may be the case with TLP type (message request with data payload).
For additional information about TLP packet headers, refer to Section 2.2.1 Common Packet Header Fields in the PCI Express Base Specification .