Cyclone® V Avalon® Memory-Mapped (Avalon-MM) Interface for PCI Express* Solutions User Guide

ID 683494
Date 10/24/2024
Public
Document Table of Contents

A.5.1. RX Block

The RX Block control logic interfaces to the hard IP block to process requests from the root complex. It supports memory reads and writes of a single dword. It generates a completion with Completer Abort (CA) status for read requests greater than four bytes and discards all write data without further action for write requests greater than four bytes.

The RX block passes header information to the Avalon‑MM master, which generates the corresponding transaction to the Avalon-MM interface. The bridge accepts no additional requests while a request is being processed. While processing a read request, the RX block deasserts the ready signal until the TX block sends the corresponding completion packet to the hard IP block. While processing a write request, the RX block sends the request to the Avalon-MM interconnect fabric before accepting the next request.