PHY Lite for Parallel Interfaces FPGA IP User Guide

ID 683716
Date 3/31/2025
Public
Document Table of Contents

2.2.2. Dynamic Reconfiguration

If you enable dynamic reconfiguration, the IP provides an ARM AMBA* AXI4-Lite interface. You can use the AXI4-Lite memory-mapped interface to reconfigure the input and output delays in the PHY and calibrate the delays. Through calibration, you can optimize the delay settings to maximize the capture window. You can access the AXI4-Lite memory-mapped interface through the EMIF Calibration IP. You can connect the EMIF Calibration IP to up to two PHY Lite for Parallel Interfaces IP instances in an I/O bank.

You can reset the PHY by enabling dynamic reconfiguration and writing to the TrainReset bit. The reset_n port in PHY Lite for Parallel Interfaces IP is a global power-up reset and resets the entire interface, including the PLL, all logic states in the I/O lanes, and the PHY dynamic reconfigurable delay control/status registers (CSR) that can be reset by the TrainReset bit.

You can reset the PHY using the following steps:

  1. Enable dynamic reconfiguration in the IP Parameter Editor GUI (pre-requisite Enable dynamic reconfiguration in the IP Parameter Editor GUI (pre-requisite).
  2. Set InternalClocksOn = 1.
  3. Set TrainReset = 1.
  4. Set TrainReset = 0.
  5. Set InternalClocksOn = 0.

The TrainReset register is internal to the I/O lane and is responsible for resetting stateful logic on both the read and write paths. This includes logic that may have become out-of-sync due to improper burst timing received during the PHY Lite IP calibration.

Altera recommends incorporating the Reset Release IP into your design to manage the reset signal for the reset_n port of the PHY Lite IP. This IP should be used to keep the PHY Lite IP in reset until the device configuration is fully complete.

The reset_n signal can remain low after configuration to delay the initialization of the PHY Lite IP. However, once the reset_n signal is set high (deactivated), it must not be reasserted to low.

You can assert the reset_n port low to reset the entire PHY Lite IP interface, which includes the IOPLL and all logic states within the I/O lanes.

Figure 13. Connection of the Calibration IP to the PHY Lite for Parallel Interfaces IP for Agilex™ 3 C-Series Devices