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

4.6.1. Transceiver Reconfiguration

Dynamic reconfiguration compensates for variations due to process, voltage and temperature (PVT). Among the analog settings that you can reconfigure are V OD, pre-emphasis, and equalization.

You can use the Altera Transceiver Reconfiguration Controller to dynamically reconfigure analog settings. For Gen2 operation, you must turn on Enable duty cycle calibration in the Transceiver Reconfiguration Controller GUI. Cyclone® V devices require duty cycle calibration (DCD) for data rates greater than 4.9152 Gbps. For more information about instantiating the Altera Transceiver Reconfiguration Controller IP core refer to Hard IP Reconfiguration .

Table 25.  Transceiver Control SignalsIn this table, <n> is the number of interfaces required.

Signal Name

Direction

Description

reconfig_from_xcvr[(<n>46)-1:0]

Output

Reconfiguration signals to the Transceiver Reconfiguration Controller.

reconfig_to_xcvr[(<n>70)-1:0]

Input

Reconfiguration signals from the Transceiver Reconfiguration Controller.

busy_xcvr_reconfig

Input

When asserted, indicates that the a reconfiguration operation is in progress.

reconfig_clk_locked

Output

When asserted, indicates that the PLL that provides the fixed clock required for transceiver initialization is locked. The Application Layer should be held in reset until reconfig_clk_locked is asserted.

The following table shows the number of logical reconfiguration and physical interfaces required for various configurations. The Quartus® Prime Fitter merges logical interfaces to minimize the number of physical interfaces configured in the hardware. Typically, one logical interface is required for each channel and one for each PLL.

Table 26.  Number of Logical and Physical Reconfiguration Interfaces

Variant

Logical Interfaces

Gen1 and Gen2 ×1

2

Gen1 and Gen2 ×2

3

Gen1 and Gen2 ×4

5

For more information about the Transceiver Reconfiguration Controller, refer to the Transceiver Reconfiguration Controller chapter in the Altera Transceiver PHY IP Core User Guide .