Modbus Guide: RTU, TCP, Registers and Troubleshooting
Practical Modbus RTU and TCP guide covering RS-485, registers, frames, function codes, CRC, raw values and troubleshooting.
Technical resources for building automation professionals, practical guidance for building owners and facility teams, and integration knowledge for equipment manufacturers.
Technical guides, troubleshooting, assessments and practical tools for engineers, integrators and commissioning professionals.
Explore resources →Practical guidance for understanding measurements, system condition, maintenance needs and building automation modernization.
Explore resources →Integration guidance and technical resources for manufacturers developing products that connect to building automation systems.
Explore resources →Practical Modbus RTU and TCP guide covering RS-485, registers, frames, function codes, CRC, raw values and troubleshooting.
Interactive air handling unit simulator with live HVAC controls, PI regulation, room dynamics, heat recovery and alarms.
Practical wireless building automation guide covering RF fundamentals, frequency bands, antennas, interference, signal quality and gateway placement.
A 30-question technical building automation assessment selected from a 120-question bank across six engineering domains.
Free online Modbus decoder and parser for Modbus RTU and Modbus TCP frames. Decode function codes, device addresses, register addresses, values, CRC results and exception responses …
A practical guide to how building automation sensors turn temperature, pressure, CO₂, humidity and other physical quantities into resistance, analog signals and digital values, …
A practical manufacturer-focused approach to Modbus register-map design, based on how PLC and BMS integrators actually consume a device interface.
A focused explanation of Modbus protocol offsets, one-based register numbers and 40001-style references with practical examples.
Learn why antenna orientation matters and how vertical versus horizontal placement can affect wireless links.
Practical RS-485 wiring checks for Modbus RTU installations that work intermittently, fail after expansion or never respond at all.
Compare 868 MHz and 2.4 GHz for building automation, including path loss, penetration, antenna size, congestion and typical use cases.
A practical method for finding why a valid Modbus response becomes the wrong engineering value in a PLC, BMS or commissioning tool.