1G/2.5G/5G/10G Multi-rate Ethernet PHY Intel® Stratix® 10 FPGA IP User Guide

ID 683876
Date 11/15/2021
Public
Document Table of Contents

6.6. Avalon® -MM Interface Signals

The Avalon® -MM interface is an Avalon® -MM slave port. This interface uses word addressing and provides access to the 16-bit configuration registers of the PHY. The following signals are synchronous to csr_clk.

Table 21.   Avalon® -MM Interface Signals
Signal Name Direction Width Description PHY Configurations
csr_address Input 5, 11 Use this bus to specify the register address to read from or write to. The width is:
  • 5 bits for 2.5G and 1G/2.5G configurations.
  • 11 bits for 1G/2.5G/10G (MGBASE-T) and 10M/100M/1G/2.5G/5G/10G (USXGMII) configurations.
All
csr_read Input 1 Assert this signal to request a read operation.
csr_readdata Output 16, 32 Data read from the specified register. The data is valid only when the csr_waitrequest signal is deasserted. The width is:
  • 16 bits for 2.5G and 1G/2.5G configurations.
  • 32 bits for 1G/2.5G/10G (MGBASE-T) and 10M/100M/1G/2.5G/5G/10G (USXGMII) configurations. The upper 16 bits are reserved.
csr_write Input 1 Assert this signal to request a write operation.
csr_writedata Input 16, 32 Data to be written to the specified register. The data is written only when the csr_waitrequest signal is deasserted. The width is:
  • 16 bits for 2.5G and 1G/2.5G configurations.
  • 32 bits for 1G/2.5G/10G (MGBASE-T) and 10M/100M/1G/2.5G/5G/10G (USXGMII) configurations. The upper 16 bits are reserved.
csr_waitrequest Output 1 When asserted, indicates that the PHY is busy and not ready to accept any read or write requests.
  • When you have requested for a read or write, keep the control signals to the Avalon® -MM interface constant while this signal is asserted. The request is complete when it is deasserted.
  • This signal can be high or low during idle cycles and reset. Therefore, the user application must not make any assumption of its assertion state during these periods.