Modbus TCP Protocol Explained | MBAP Header, Frame Structure & Practical Example

Understand the *Modbus TCP protocol* and learn how Modbus messages are structured and transmitted over Ethernet using TCP/IP. In this tutorial, we break down the *Modbus TCP frame* and explain the ADU, PDU, and 7-byte MBAP header. We go through the Transaction Identifier, Protocol Identifier, Length, and Unit Identifier fields, and understand how each one is used when a Modbus TCP client communicates with a server. #STM32 #ModbusTCP #LWIP #EmbeddedSystems 📁 *Modbus TCP Frame Explained:* https://controllerstech.com/modbus-tcp-protocol-explained/ 📁 *Download the pdf here:* https://controllerstech.com/wp-content/uploads/2026/04/ModbusTCP.pdf 📁 *STM32 Modbus TCP Series:* https://controllerstech.com/stm32-hal/modbus/tcp-tutorials/ 📁 *ControllersTech Home:* https://controllerstech.com/ ### ▶︎ Related Videos 1️⃣ *STM32 Modbus TCP Server – Part 1:* https://youtu.be/uQCWLD-066s 2️⃣ *STM32 Modbus TCP Series Playlist:* https://www.youtube.com/playlist?list=PLJ2wq5MP9BTo