User's Manual
Table Of Contents
- Contents
- Safety Notice
- 1 Introduction
- 2 Setup
- 3 Data Structure
- 4 Web Control
- 5 PandarView
- 6 Communication Protocol
- 7 Sensor Maintenance
- 8 Troubleshooting
- Appendix I Channel Distribution
- Appendix II Absolute Time and Laser Firing Time
- Appendix III PTP Protocol
- Appendix IV Phoenix Contact
- Appendix V Nonlinear Reflectivity Mapping
- Appendix VI Certification Info
- Appendix VII Support and Contact
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6 Communication Protocol
To ensure real-time communication, Hesai’s TCP protocol uses binary format and has disabled Nagle’s algorithm.
6.1 Packet Structure
A client can send command messages to the server (LiDAR). Each command message includes a fixed 8-byte header and a variable command-specific
payload. The header describes the command type and payload length.
Table 6.1 Command Message Sent from Client to LiDAR
Type
Length
Field Description
0x47
1 byte
Fixed content
0x74
1 byte
Fixed content
Cmd
1 byte
Command code. See Section 6.2 Command Description
Return Code
1 byte
Useless
Payload Length
4 bytes
Data length for the command 0x00 – no payload
Payload
Indicated in Payload Length
Additional data for the command
The server (LiDAR) outputs a feedback message for every command it receives.
Table 6.2 Feedback Message from LiDAR to Client
Type
Length
Field Description
0x47
1 byte
Fixed content
0x74
1 byte
Fixed content
Cmd
1 byte
Command code
Return Code
1 byte
Return code from server
Data Length
4 bytes
Data length for the command 0x00 – no payload
Payload
Indicated in Payload Length
Additional data for the command