Topic
Serial
2 guides across the knowledge base.
TroubleshootingTroubleshootingModbus
Modbus Device Intermittently Offline
A device that answers most of the time. Termination, bias, timing, and the physical layer details that produce a bus which almost works.
9 min readUpdated Aug 21, 2026
ReferenceCommunicationsModbus
Modbus RTU
Serial Modbus over RS-485: function codes, register addressing, the off-by-one that catches everyone, and the physical layer details that decide whether a bus is stable.
10 min readUpdated Jul 21, 2026
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