ModbusRtuService class

Low-level Modbus RTU framing primitives.

Supports FC03 (Read Holding Registers) as required by the soil sensor. All multi-byte values are big-endian on the wire; CRC is sent lo-byte first.

Constructors

ModbusRtuService()

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

buildReadRequest({required int slaveAddress, required int startRegister, required int registerCount}) → Uint8List

Build an FC03 Read Holding Registers request (8 bytes).

calculateCrc16(Uint8List data, int length) → int

Calculates the CRC-16/ANSI (Modbus) checksum for length bytes of data.

expectedResponseLength(int registerCount) → int

Expected total response length for FC03 with registerCount registers. Formula: 3 (addr + fc + byteCount) + registerCount*2 + 2 (CRC)

parseReadResponse(Uint8List response, int registerCount) → List<int>

Parse and validate an FC03 response.

scaleBasicRegisters(List<int> raw) → Map<String, double>

Scale 3 raw register values (basic sensor: moisture, temp, conductivity).

scaleExtendedRegisters(List<int> raw) → Map<String, double>

Scale 7 raw register values into physical quantities.