RS485 Communication Between PLC Modbus Master and Arduino Modbus Slave

[@mohamedshalby9741]

Good morning Sir.... Can I connect delta plc master to two slave arduino by using rs485...... I need to know the program of Delta PLC master......thanks

[@saurabhbijenian]

hello, can you please help me connect Delta as228t with arduino, i wanted plc to read the load cell data from arduino uno

[@1vlcsnap]

Hello, I have a problem, everything is fine, compile, load, the signal commands work, but when the program works for a while, the Arduino does nothing, stops and stops responding. please help me :).

[@carlosmocadan9580]

Greetings great project, I was wondering if it would be possible to program the plc s7200 by microwin incorporating a usb-ttl converter (PL2303) to the max485 module of your video?

[@tharunmax4406]

this program is not working help me to figure it out

[@eurekaenglish8405]

please create content about raspberry pi communication with PLC via the modbus protocol

[@arayarock1]

do you use 3x 4x register?

[@mohitsingh5665]

Well while compiling it is showing no matching function for call to modbus slave setBaud(hardwareSerial, int, int, int)

[@sivaskt]

did you got any solution for this

[@mohitsingh5665]

I have designed my own Arduino based modbus device that can read and write to PLC.

[@sivaskt]

sir where you from, any help to us figure out the issue

[@mohitsingh5665]

Delhi, what is the issue please feel free to discuss

[@sivaskt]

can u share email id

[@ปกสีดํา]

How to Arduino Modbus Master.

[@詹博任-e6o]

have problem :setBaud(hardwareSerial, int, int, int)

[@詹博任-e6o]

Are you really successful ?

[@mohitsingh5665]

Any solution ???

[@peterkurtosi]

Hi, first of all, this is a great tutorial. I downloaded your library from blogspot and built a slave device from Arduino Mega. The communication with my Master device is perfect around 3 minutes and 40 seconds. Then my Arduino reboots itself. The booting process is so fast that it is within the Master's timeout, so the communication proceeds, however with the initial values obviously. If I increase the delay in your modbusSlave.cpp file like this: free(_msg); delay(_len*7); the reboot never happens. However, a delay at a Modbus slave device is "life threatening". :) Does anybody have any idea, advice etc. why it happens and what can be the solution? Thanks for any idea.

[@plc4u]

+Peter Kurtosi good information. thanks.

[@peterkurtosi]

+plc4u I think, here is the problem with this Modbus library: arduino.stackexchange.com/questions/682/is-using-malloc-and-free-a-really-bad-idea-on-arduino I wrote a small function and added to this library to track the memory size. At UNO, the memory runs out during ~30 seconds, at MEGA ~3 minutes and 40 seconds. (of course this period of time depends on the master's requests (in my case 60ms)). Unfortunately, have to overwrite the library with static memory allocation. :(

[@dilipghodasara9491]

Problem :- setBaud(hardwareSerial, int, int, int)

[@pradeepks6992]

PLC MODEL NO

[@charlesdelv.6049]

good job!!!!!

[@plc4u]

+Charles Del Villar Quintero OK.

[@user-tatara4]

So