LVDS Tunneling Protocol and Interface (LTPI) IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs

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ID 844310
Date 8/15/2025
Public
Document Table of Contents
Document Table of Contents x
1. Overview 2. Configuring and Generating the IP 3. Simulating the IP 4. Validating the IP 5. Troubleshooting and Debugging Issues 6. Appendix A: Functional Description 7. Appendix B: Registers 8. Document Revision History for the LVDS Tunneling Protocol and Interface (LTPI) IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs
1. Overview x
1.1. About the LVDS Tunneling Protocol and Interface (LTPI) IP 1.2. About the Document 1.3. Applicable Applications 1.4. Key Concepts 1.5. IP Design Flow 1.6. Design Considerations/Guidelines
1.1. About the LVDS Tunneling Protocol and Interface (LTPI) IP x
1.1.1. IP Release Information 1.1.2. IP Features 1.1.3. IP High-level Block Diagram 1.1.4. Licensing the IP 1.1.5. Device Family Support 1.1.6. Device Speed Grade Support 1.1.7. IP Core Support Levels 1.1.8. IP Performance and Resource Utilization
1.2. About the Document x
1.2.1. Target Audience 1.2.2. Conventions Used in the Document 1.2.3. Acronyms 1.2.4. Reference Documents and Training
1.4. Key Concepts x
1.4.1. Interface Tunneling Principle 1.4.2. LTPI Tunneling Methodology 1.4.3. Clock Topology 1.4.4. LTPI Frame 1.4.5. System-level Block Diagram 1.4.6. Link Management 1.4.7. Signal Description
1.4.4. LTPI Frame x
1.4.4.1. Link Detect and Link Speed Selection Frames 1.4.4.2. Link Detect Frame 1.4.4.3. Link Speed Frame 1.4.4.4. Advertise, Configure, and Accept Frames 1.4.4.5. Advertise Frames 1.4.4.6. Configure Frame 1.4.4.7. Accept Frame 1.4.4.8. LTPI Operational Frames 1.4.4.9. Default I/O Frame 1.4.4.10. Default Data Frame
1.4.6. Link Management x
1.4.6.1. Link Training 1.4.6.2. Link Configuration 1.4.6.3. Operational Mode
1.4.7. Signal Description x
1.4.7.1. Clock and Power Signals 1.4.7.2. Channel Signals 1.4.7.3. Avalon® Memory-Mapped Primary Interface Signals 1.4.7.4. Avalon® Memory-Mapped Secondary Interface Signals 1.4.7.5. Avalon® Memory-Mapped CSR Interface Signals 1.4.7.6. Miscellaneous Interface Signals
2. Configuring and Generating the IP x
2.1. Configuring the Quartus® Prime Pro Edition Project 2.2. Configuring the LVDS Tunneling Protocol and Interface (LTPI) IP 2.3. Generating HDL for Synthesis and Simulation 2.4. Generating the Simulation Design Example
2.2. Configuring the LVDS Tunneling Protocol and Interface (LTPI) IP x
2.2.1. Configuring the LVDS Tunneling Protocol and Interface (LTPI) IP Parameters
2.3. Generating HDL for Synthesis and Simulation x
2.3.1. Generated File Structure
2.4. Generating the Simulation Design Example x
2.4.1. Generated Directory Structure and Files
3. Simulating the IP x
3.1. Design Example Features 3.2. Design Example Components 3.3. Configuring the Design Example Parameters 3.4. Simulating the Design Example
3.4. Simulating the Design Example x
3.4.1. Simulation Testbench Flow 3.4.2. Simulation Output
4. Validating the IP x
4.1. Validating the IP Using Agilex™ 5 Device
4.1. Validating the IP Using Agilex™ 5 Device x
4.1.1. Compiling the Design Example in Hardware on Agilex™ 5 Device 4.1.2. Validating the Design Example in Hardware on Agilex™ 5 Device
4.1.2. Validating the Design Example in Hardware on Agilex™ 5 Device x
4.1.2.1. Configuring the Clocks in Hardware 4.1.2.2. Programming the FPGA 4.1.2.3. Running the Hardware Test
6. Appendix A: Functional Description x
6.1. GPIO Channel 6.2. I2C Channel 6.3. UART Channel 6.4. Data Channel 6.5. OEM Channel
1. Overview
2. Configuring and Generating the IP
3. Simulating the IP
4. Validating the IP
5. Troubleshooting and Debugging Issues
6. Appendix A: Functional Description
7. Appendix B: Registers
8. Document Revision History for the LVDS Tunneling Protocol and Interface (LTPI) IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs

1.4.2. LTPI Tunneling Methodology

The LTPI IP supports interfaces like GPIO, I2C/SMbus, UART, OEM, and data by packetizing their signals into frames and transmitting them over the LVDS interface using time-division multiplexing (TDM).

As shown in the following figure, each frame is sent in equal time slots, with bits assigned based on the bandwidth needed for each channel. Frames are sent back-to-back without inter-frame gaps to reduce latency.

Figure 4. LTPI Channel Encapsulation and Serialization using TDM Method
Level Two Title