@iobroker/modbus

This is a library that allows you to implement ioBroker Adapter that communicates via ModBus with devices.

It could accept TSV file as a configuration. TSV files could be created as export in ioBroker.modbus adapter.

Usage

You can find an example here.

$3

``typescript
import ModbusTemplate, { tsv2registers } from '@iobroker/modbus';
import type { AdapterOptions } from '@iobroker/adapter-core';
import { readFileSync } from 'node:fs';
const adapterName = JSON.parse(readFileSync(${__dirname}/../io-package.json, 'utf8')).common.name;

export class ModbusAdapter extends ModbusTemplate {
public constructor(adapterOptions: Partial = {}) {
const holdingRegs = tsv2registers('holdingRegs', ${__dirname}/../data/holdingRegs.tsv);

super(
adapterName,
adapterOptions,
{
params: {
// Do not show addresses in the object IDs
doNotIncludeAdrInId: true,
// Remove the leading "_" in the names
removeUnderscorePrefix: true,
// Do not show aliases, because we don't want to see addresses
showAliases: false,
// Replace holdingRegister (and so on) with "data" in the object names
registerTypeInName: 'data',
},
holdingRegs,
},
);
}
}

// If started as allInOne mode => return function to create instance
if (require.main !== module) {
// Export the constructor in compact mode
module.exports = (options: Partial | undefined) => new ModbusAdapter(options);
} else {
// otherwise start the instance directly
(() => new ModbusAdapter())();
}
`

$3

`javascript
const IoBrokerModbus = require ('@iobroker/modbus');
const { readFileSync } = require('node:fs');
const adapterName = JSON.parse(readFileSync(${__dirname}/../io-package.json, 'utf8')).common.name;

export class ModbusAdapter extends ModbusTemplate {
public constructor(options) {
const holdingRegs = tsv2registers('holdingRegs', ${__dirname}/../data/holdingRegs.tsv);

super(adapterName, options, { holdingRegs });
}
}

// If started as allInOne mode => return function to create instance
if (require.main !== module) {
// Export the constructor in compact mode
module.exports = options => new ModbusAdapter(options);
} else {
// otherwise start the instance directly
(() => new ModbusAdapter())();
}
`

$3

`typescript
import ModbusTemplate, { tsv2registers } from '@iobroker/modbus';
import type { AdapterOptions } from '@iobroker/adapter-core';
import { readFileSync } from 'node:fs';
const adapterName = JSON.parse(readFileSync(${__dirname}/../io-package.json, 'utf8')).common.name;

export class ModbusAdapter extends ModbusTemplate {
public constructor(options: Partial = {}) {
super(
adapterName,
options,
{
params: {
port: 520, // you can override all parameters here
},
parameterNameForFile: 'deviceType', // name of the attribute in config to read files from
adapterRootDirectory: ${__dirname}/.., // adapter diractory
}
);
}
}

// If started as allInOne mode => return function to create instance
if (require.main !== module) {
// Export the constructor in compact mode
module.exports = (options: Partial | undefined) => new ModbusAdapter(options);
} else {
// otherwise start the instance directly
(() => new ModbusAdapter())();
}
`

In the second example the adapter will read from its configuration attribute deviceType the type of the device and tries to find file:

- / - holding registers
- or /inputRegs.tsv - for input registers

If the value of deviceType is data/holdingRegs.tsv or data/holdingRegs the adapter will search for file /data/holdingRegs.tsv.

If the value of deviceType is data/m100.tsv or data/m100 the adapter will search for files /data/m100coils.tsv, /data/m100disInputs.tsv, /data/m100inputRegs.tsv, /data/m100holdingRegs.tsv

Serial port

If you want to use serial port, you have to include serialport package into 'package.json' of your adapter, because @iobroker/modbus does not have this dependency by default.

Test

There are some programs in folder test to test the TCP communication:

- Ananas32/64 is a slave simulator (only holding registers and inputs, no coils and digital inputs)
- RMMS is master simulator
- mod_RSsim.exe is a slave simulator. It can be that you need Microsoft Visual C++ 2008 SP1 Redistributable Package to start it (because of Side-By-Side error).

Changelog

- (@GermanBluefox) Added onBeforeReady method to do something before adapter starts

$3

- (@GermanBluefox) Added host parameter for master connection

$3

- (@GermanBluefox) Added removeUnderscorePrefix parameter
- (@GermanBluefox) Added noRegisterTypeInName` parameter
- (@GermanBluefox) Allowed to set custom channel name

$3

- (bluefox) initial commit

License

The MIT License (MIT)

Copyright (c) 2015-2025 Bluefox

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.