Template for Modbus protocol in ioBroker
npm install @iobroker/modbusThis 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.
You can find an example here.
``typescript${__dirname}/../io-package.json
import ModbusTemplate, { tsv2registers } from '@iobroker/modbus';
import type { AdapterOptions } from '@iobroker/adapter-core';
import { readFileSync } from 'node:fs';
const adapterName = JSON.parse(readFileSync(, 'utf8')).common.name;
export class ModbusAdapter extends ModbusTemplate {
public constructor(adapterOptions: Partial
const holdingRegs = tsv2registers('holdingRegs', ${__dirname}/../data/holdingRegs.tsv);
super(
adapterName,
adapterOptions,
{
params: {
// Do not show addresses in the object IDs
doNotIncludeAdrInId: true,
// Remove the leading "_" in the names
removeUnderscorePrefix: true,
// Do not show aliases, because we don't want to see addresses
showAliases: false,
// Replace holdingRegister (and so on) with "data" in the object names
registerTypeInName: 'data',
},
holdingRegs,
},
);
}
}
// If started as allInOne mode => return function to create instance
if (require.main !== module) {
// Export the constructor in compact mode
module.exports = (options: Partial
} else {
// otherwise start the instance directly
(() => new ModbusAdapter())();
}
`
`javascript${__dirname}/../io-package.json
const IoBrokerModbus = require ('@iobroker/modbus');
const { readFileSync } = require('node:fs');
const adapterName = JSON.parse(readFileSync(, 'utf8')).common.name;
export class ModbusAdapter extends ModbusTemplate {
public constructor(options) {
const holdingRegs = tsv2registers('holdingRegs', ${__dirname}/../data/holdingRegs.tsv);
super(adapterName, options, { holdingRegs });
}
}
// If started as allInOne mode => return function to create instance
if (require.main !== module) {
// Export the constructor in compact mode
module.exports = options => new ModbusAdapter(options);
} else {
// otherwise start the instance directly
(() => new ModbusAdapter())();
}
`
`typescript${__dirname}/../io-package.json
import ModbusTemplate, { tsv2registers } from '@iobroker/modbus';
import type { AdapterOptions } from '@iobroker/adapter-core';
import { readFileSync } from 'node:fs';
const adapterName = JSON.parse(readFileSync(, '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
} 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 - for input registers
If the value of deviceType is data/holdingRegs.tsv or data/holdingRegs the adapter will search for file .
If the value of deviceType is data/m100.tsv or data/m100 the adapter will search for files , , ,
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.
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).
- (@GermanBluefox) Updated packages
- (@GermanBluefox) Corrected serial communication
- (@GermanBluefox) Added onBeforeReady method to do something before adapter starts
- (@GermanBluefox) Added host parameter for master connection
- (@GermanBluefox) Added removeUnderscorePrefix parameternoRegisterTypeInName` parameter
- (@GermanBluefox) Added
- (@GermanBluefox) Allowed to set custom channel name
- (bluefox) initial commit
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