PLC Communication Protocol with Siemens PLC

PLC Communication Protocol with Siemens PLC

1. Protocol Reverse Engineering Record (Wireshark Capture Code) # Wireshark filter rule (key fields marked in red)tcp.port == 102 && cotp && s7comm /* Typical handshake message structure 0000 03 00 00 16 11 e0 [TSAP:0x0100] [TSAP:0x0101] 00 00 00 01 00 c0 01 0a |_________| |___| |_____________| |_____________| |_TPKT_| |_COTP_| |S7C| */ #pragma pack(1) … Read more

Modbus Communication Protocol Explained

Modbus Communication Protocol Explained

Click the “Technical Training” above and select “Pin to Public Account” Over 150,000 industrial control professionals follow this WeChat platform: technical sharing, learning exchanges, industrial control videos The day before yesterday, I discovered a true fan who comments every day on the articles shared by Technical Training. He suggested that I share some content on … Read more

Detailed Explanation and Case Demonstration of Modbus Protocol

Detailed Explanation and Case Demonstration of Modbus Protocol

The Modbus RTU communication protocol uses a master-slave response method for data communication. Requests can only be initiated by the master (PC, HMI, etc.) through a unique slave address, and the slave (terminal device) responds to the master’s requests, thus enabling half-duplex communication. This protocol only allows the master to initiate requests, and the slave … Read more

Solutions for EMMC Socket Read/Write Errors

Solutions for EMMC Socket Read/Write Errors

EMMC Socket Usage: Enter “EMMC” under “Input Chip Marking” to see the following three options: EMMC_AUTO: Speed 8BIT (default), automatically recognized when EMMC. EMMC_AUTO_4BIT: 4BIT, recommended for most chips for stability. EMMC_AUTO_1BIT: 1BIT, can be selected when the above two cannot read; slower speed but may recover data in the chip. Additionally, the chip model … Read more

Understanding the Modbus Communication Protocol

Understanding the Modbus Communication Protocol

The Most Comprehensive Free Industrial Control Software! (Click the red text above to get free materials) Introduction:The ModBus network is an industrial communication system formed by connecting programmable controllers with intelligent terminals and computers through common lines or local private lines. Its system structure includes both hardware and software. It can be used for various … Read more

Understanding the Modbus Communication Protocol

Understanding the Modbus Communication Protocol

The ModBus network is an industrial communication system formed by connecting programmable controllers with intelligent terminals and computers through public or local dedicated lines. Its system structure includes both hardware and software. It can be applied to various data acquisition and process monitoring. The ModBus network has only one master, and all communication is initiated … Read more

Understanding Modbus Communication Protocol

Understanding Modbus Communication Protocol

ModBus network is an industrial communication system formed by connecting programmable controllers with intelligent terminals and computers through public or local dedicated lines. Its system structure includes both hardware and software. It can be applied to various data acquisition and process monitoring. The ModBus network has only one master, and all communication is initiated by … Read more

Understanding the Modbus Communication Protocol

Understanding the Modbus Communication Protocol

Modbus Communication Protocol Introduction: The ModBus network is an industrial communication system formed by connecting programmable controllers with intelligent terminals and computers via public or local dedicated lines. Its system structure includes both hardware and software. It can be applied to various data acquisition and process monitoring. The ModBus network has only one master, and … Read more

Understanding The Modbus Communication Protocol

Understanding The Modbus Communication Protocol

Follow the “Automation Control System Communication” public account to understand the principles of automation control systems and master the knowledge of automation control systems. Click the blue “Automation Control System Communication” above to follow us. Understanding what the Modbus communication protocol is allows you to perform communication tests on-site using various third-party software. The Modbus … Read more

Why Does SPI DMA Circular Reception Fail When CRC Is Enabled?

Why Does SPI DMA Circular Reception Fail When CRC Is Enabled?

Someone is using the STM32G4 internal SPI configured as a slave full-duplex mode, using DMA for receiving. When the DMA is configured to CIRCULAR mode, problems occur where data transmission results in CRC verification failures and reception anomalies. If the DMA transfer mode is configured to NORMAL, there are no issues, and the received data … Read more