Quartus® Prime Pro Edition User Guide: Debug Tools

ID 683819
Date 12/09/2025
Public
Document Table of Contents

8. Remote Debugging

Remote debugging in Quartus® Prime software is debugging your application on the FPGA without physically connecting or accessing any pins on your FPGA board. The debugging communication can occur over a TCP/IP network (where the FPGA board host and the debugging system are separate devices) or a PCIe interface (where the FPGA board resides in the PCIe slot in the same system that is used for debugging).

The primary tool for remote debugging is the High-Speed Streaming (HS ST) Interface IP. This IP supports debugging over JTAG and Avalon® MM interfaces, which gives you flexibility in your remote debugging implementation.

For remote debugging via the Avalon® Memory Mapped Interface, you can access the debug infrastructure within an FPGA in the following ways:
  • using high-speed streaming interface
  • using JTAG-over-protocol interface

The High-Speed Streaming (HS ST) Interface IP supersedes the JTAG-Over-Protocol IP.For new designs, use the HS ST Interface IP. For existing designs that use the JTAG-Over-Protocol IP, refer to AN 971: JTAG-Over-Protocol FPGA IP.

Table 49.  Debug Interface Pros and ConsThe following chart shows the pros and cons for each architecture to help you determine which architecture to use.
Debug Interface Pros Cons

Local JTAG

  • Little setup required; Just connect a USB Blaster FPGA Development Cable.
  • Debug infrastructure is automated
  • Slower than streaming solution
  • Requires physical JTAG connection to board
HS ST Interface IP using high-speed streaming debug interface
  • Can use different debug channels (for example, PCIe or Ethernet)
  • Allows for remote debug over debug channels
  • Fastest offloading of debug data due to native streaming interface throughout debug infrastructure
  • Allows switching between remote debug channel and JTAG interface at run time.
  • Requires setup for the communication infrastructure and debug server
  • Currently, only Signal Tap , Avalon® MM Debug Bridge, and AXI MM Debug Bridge can use the streaming debug interface.

HS ST Interface IP using JTAG-over-protocol interface

  • Can use different debug channels (for example, PCIe or Ethernet)
  • Allows for remote debug over debug channels
  • Supports all existing debug endpoints with JTAG interface
  • Uses JTAG in underlying debug infrastructure, which is slower than HS ST debug interface
  • Requires setup for the communication infrastructure and debug server
  • The generated JTAG clock presents some timing closure challenge; the TCK-ENA using system clock is usable for compatible JTAG-based logic.