Reference
2 articles tagged "Reference" on the Modbus Poll blog.
This collection brings together every Reference article published on the Modbus Poll blog. "Modbus Function Codes Explained: FC01–FC06, FC15, FC16 (2026 Reference)", "Modbus Addressing Explained: PLC Address vs Protocol Address (No More Off-By-One)" — each one is a practical, hands-on guide written for engineers and system integrators who work with Modbus Poll in real industrial deployments. Whether you are choosing between protocols, troubleshooting a connection, or planning an integration, these articles cover the concepts, the trade-offs, and the step-by-step details you need.
Modbus Function Codes Explained: FC01–FC06, FC15, FC16 (2026 Reference)
Every standard Modbus function code explained: FC01 read coils, FC03 read holding registers, FC06 write single register, FC16 write multiple. Request/response frame layout, byte order, and when to use each code.
Read articleModbus Addressing Explained: PLC Address vs Protocol Address (No More Off-By-One)
Why Modbus holding register 40001 is protocol address 0. The PLC address vs protocol address off-by-one confusion, the four address ranges, and how to convert between them.
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