Unit ID modbus stream

[Mohamedelhrichi]

Unit ID modbus stream

[dresende]

If you're using a serial device..

const modbus = require("modbus");

modbus.serial.connect("/dev/ttyUSB0", { slaveId: 245 },(err, connection) => {
    // ...
    // connection.readCoils(...)
});

If you're using TCP...

const modbus = require("modbus");

modbus.tcp.connect("192.168.253.78", { unitId: 245 },(err, connection) => {
    // ...
    // connection.readCoils(...)
});

[Mohamedelhrichi]

tank you a lot for you answer.
I tested this but i have the same probleem when a add a salveid option

var modbus = require("modbus-stream");

 function readclient(ip) {
     modbus.tcp.connect(502, ip,{ slaveId: 245} , { debug: "automaton-2454" }, (err, connection) => {
console.log("connected")
connection.readCoils({ address: 0, quantity: 10 }, (err, res) => {
    if (err) throw err;

    console.log(res.response.data); // response
})
});
 }
 readclient("127.0.0.1") ;

i have receved this message

Error: GatewayTargetDeviceFailedToRespond
    at Object.exports.error (C:\Users\RAYAN\Desktop\mod\node_modules\modbus-pdu\lib\Exception.js:24:13)
    at Timeout._onTimeout (C:\Users\RAYAN\Desktop\mod\node_modules\modbus-stream\lib\transport\transport.js:93:33)
    at ontimeout (timers.js:482:11)
    at tryOnTimeout (timers.js:317:5)
    at Timer.listOnTimeout (timers.js:277:5) 

[dresende]

slaveId does not exist in TCP, only unitId. I fixed my previous example.

[Mohamedelhrichi]

thank you for your answers i rectified my code but it's give the same error

var modbus = require("modbus-stream");
function readclient(ip) {
modbus.tcp.connect( 502, ip,{unitId : 245} ,
{ debug: "automaton-2454" }, (err, connection) => {
console.log("connected")
connection.readInputRegisters({ address: 0, quantity: 10 }, (err, res) => {
if (err) throw err;

console.log(res.response.data); // response

})
});
}

readclient("127.0.0.1") ;

Error: GatewayTargetDeviceFailedToRespond
at Object.exports.error (C:\Users\RAYAN\Desktop\mod\node_modules\modbus-pdu\lib\Exception.js:24:13)
at Timeout._onTimeout (C:\Users\RAYAN\Desktop\mod\node_modules\modbus-stream\lib\transport\transport.js:93:33)
at ontimeout (timers.js:482:11)
at tryOnTimeout (timers.js:317:5)
at Timer.listOnTimeout (timers.js:277:5)

[dresende]

Do you have a modbus client on your computer? Are you sure it's on port 502 and responds to that request?

[Mohamedelhrichi]

i tested with to read my modbus client with node modbus stream ...doesnt work and its gives this error
GatewayPathUnavailable..
but with QmODMASTER it's works perfectely with no probelem
you can see picture
i think that the probelem is in {unitId : 245} parameter
You can see picture
error with node modbus stream
https://drive.google.com/file/d/1AgQh34inx2uvocBD500JRt4DupUii2rC/view?usp=sharing

result with QmODMASTER software
https://drive.google.com/file/d/1BqxfhrceQcQFziSajPmZBLikHdCKgKrX/view?usp=sharing

full error messagewith node modbus stream

$ node index.js
connected
2018-10-20T12:01:37.346Z << automaton-2454 0x[ 00, 01, 00, 00, 00, 06, 01, 04, 01, 03, 00, 0A ]
2018-10-20T12:01:37.441Z >> automaton-2454 0x[ 00, 01, 00, 00, 00, 03, 01, 84, 0A ]
events.js:183
      throw er; // Unhandled 'error' event
      ^

Error: GatewayPathUnavailable
    at handle (C:\Users\1\Desktop\mod\node_modules\modbus-stream\lib\transport\transport.js:127:19)
    at Socket.<anonymous> (C:\Users\1\Desktop\mod\node_modules\modbus-stream\lib\transport\transport.js:183:3)
    at emitOne (events.js:116:13)
    at Socket.emit (events.js:211:7)
    at addChunk (_stream_readable.js:263:12)
    at readableAddChunk (_stream_readable.js:250:11)
    at Socket.Readable.push (_stream_readable.js:208:10)
    at TCP.onread (net.js:597:20)

1@1-PC MINGW32 ~/Desktop/mod (master)
$ node index.js
connected
2018-10-20T12:03:09.137Z << automaton-2454 0x[ 00, 01, 00, 00, 00, 06, 01, 04, 01, 03, 00, 0A ]
2018-10-20T12:03:09.199Z >> automaton-2454 0x[ 00, 01, 00, 00, 00, 03, 01, 84, 0A ]
events.js:183
      throw er; // Unhandled 'error' event
      ^

Error: GatewayPathUnavailable
    at handle (C:\Users\1\Desktop\mod\node_modules\modbus-stream\lib\transport\transport.js:127:19)
    at Socket.<anonymous> (C:\Users\1\Desktop\mod\node_modules\modbus-stream\lib\transport\transport.js:183:3)
    at emitOne (events.js:116:13)
    at Socket.emit (events.js:211:7)
    at addChunk (_stream_readable.js:263:12)
    at readableAddChunk (_stream_readable.js:250:11)
    at Socket.Readable.push (_stream_readable.js:208:10)
    at TCP.onread (net.js:597:20)

[Mohamedelhrichi]

hello it's OK now it's worked with this code

//var modbus = require("modbus-stream");
const modbus = require("modbus-stream");
var fs = require('fs') ;

 var mydata ;
 var mydata2 ;
 var mydata3 ="bonjour" ; 

 function readclient(ip) {
   

    modbus.tcp.connect(ip, { unitId: 245 },(err, connection) => {
        // ...
        connection.readInputRegisters({ address: 259, quantity: 20 }, (err, res) => {
            if (err) throw err;
        
            console.log(res); 
            mydata = res.response.data ;
            // response
            mydata2=res.pdu ;
            
         //  mydata3 = mydata2.toString('utf8') ;
          //  var ret = mydata3.replace(/Buffer-/g,'');
         //   var ret2 = ret.replace(/<-/g,'');
          //  var ret3 = ret2.replace(/>-/g,'');
          //  mydata3 = ret3 ;
          //  console.log(mydata3) ;
            
      
        })
        });
 }

 //,{ slaveId: 1}
 readclient("10.80.15.62") ;

[Mohamedelhrichi]

i want to know how a can use buffer data and convert it to int array or decimal array

[dresende]

Modbus does not define any types for data, you need to know how and what they have encoded. Show me the response (res or just res.response.data) and tell me what it should have there.

[Mohamedelhrichi]

ok thanks its OK a wondefull module thanks a lot

[sarat12]

Thanks for the decent peace of software! Is there any chance to change slaveId using the same connection? (I do polling on serial port and want to keep connection opened).

[sarat12]

Sorry for bothering, just figured that out:
connection.transport.slaveId = slaveId;

[dresende]

😉