External Memory Interface Handbook Volume 3: Reference Material: For UniPHY-based Device Families

ID 683841
Date 3/06/2023
Document Table of Contents Nios II-based Sequencer Architecture

The sequencer is composed of a Nios II processor and a series of hardware-based component managers, connected together by an Avalon bus. The Nios II processor performs the high-level algorithmic operations of calibration, while the component managers handle the lower-level timing, memory protocol, and bit-manipulation operations.

The high-level calibration algorithms are specified in C code, which is compiled into Nios II code that resides in the FPGA RAM blocks. The debug interface provides a mechanism for interacting with the various managers and for tracking the progress of the calibration algorithm, and can be useful for debugging problems that arise within the PHY. The various managers are specified in RTL and implement operations that would be slow or inefficient if implemented in software.

Figure 6. NIOS II-based Sequencer Block Diagram

The C code that defines the calibration routines is available for your reference in the \<name>_s0_software subdirectory. Intel recommends that you do not modify this C code.