Modbus RTU (serial port) does not work with new kernel version ^{CODESYS Forge talk (Thread)}
Modbus RTU (serial port) does not work with new kernel version
Last updated: 2025-05-13

Post by struccc on Problem Reading Registers via Modbus from non Codesys device ^{CODESYS Forge talk (Post)}
Hi, Might be a good idea first to try out the connection and the device with some handy software, like Modbus Poll. There you can see better, what's really going on... - Is it really connected? - What error code does it return? - Can it read from the register address? - Maybe try Input registers and Holding Registers - can make a difference - Sometimes register addresses are messed up: shifted +-1 (mixing of 2 standards) - Sometimes register addresses start with offset 30000, 40000 ... - Are you using the right protocol? - Is it RTU or TCP? Maybe ASCII? - Can even have a look at the data packets, etc... All this is easier to figure out first with some modbus utility... and then to set it up in CODESYS should not be an issue. P.
Last updated: 2025-03-09

Post by mbmik on IoDrvModbusTCP_Diag not defined when using MODBUS ^{CODESYS Forge talk (Post)}
Hi Im trying to setup a Weidmüller WL2000 to run with MODBUS, to get some data from a server. Codesys V3.5 SP20. The issue is, that whenever i attach an ethernet port and add MODBUS Master und also a Slave, codesys will compile the project, but there always seem to be some remaining errors, which or only visible, when setting the messages window to "Pre-Compiled". I tried a lot of stuff to get rid of these errors, but cant find to seem the reason. New installation of codesys, cleaned project, setup completely empty new project, manually adding libs. Nothing helps. Any help is apreciated. Maybe we are doing something wrong.. Example Project is available, if somebodey wants to take a look. Greetings and thanks alot
Last updated: 2024-04-15

Post by elsmart on Sequential read and triggering of Modbs RTU channels in application ^{CODESYS Forge talk (Post)}
Hello I need some help understanding how to use Modbus RTU (COM port) in Codesys enviroment. I defined a Modbus Server device (slave) in device tree and added some channels to read from (function 3). Also I set trigering mode to Application. I have a POU in which I want to trigger each channel one after the other something like this (C code for better visualisation): for (int i = 0; i < channelsCount; i++) { triggerChannel(channelsArray[i]); // Start transmission while(channel.xBusy); // Wait for transmission to complete } I have found ModbusChannel function block documentation but examples are scarce. I don't understand how rising edge triggering works. What would be the best solution for achieving sequntial channel triggering? What is the common way to read multiple Modbus channels once every time a specified POU is executed?
Last updated: 2025-05-16

Post by ahuckphin on Issues with Modbus Slave with Raspberry Pi ^{CODESYS Forge talk (Post)}
I have a DFRobot RS485 temperature & humidity sensor (SEN0438) connected to my Raspberry Pi via a USB to RS485 adapter. I am able to connect and read the sensor data when running a python code locally. However in Codesys, I encounter this error "A bus error has occurred." and "There was no response in time". Could this be because of Modbus Server Channel and Modbus Server Init configuration on my part? Admittedly I am new to Codesys. To get to this stage, I: 1. added some lines to CODESYSControl_User.cfg 2. added "Modbus_COM" in Codesys and set "Serial Port Configuration" under "General" 3. added "Modbus_Master_COM_Port" in Codesys and checked transmission mode is set to "RTU" 4. added "Modbus_Slave_COM_Port" in Codesys and checked server address is set to 1 (also set 1 in my sensor) 5. added 1 channel and 1 init for "Modbus_Slave_COM_Port" under "Modbus Server Channel" and "Modbus Server Init"
Last updated: 2024-07-10

Post by george32 on TCP Server ^{CODESYS Forge talk (Post)}
Dear people, I would like to create a TCP server in my PLC program. The TCP server needs to communicate with an external device. I have been searching the internet and found that the libraries Syssocket or CAA NetBaseSrv are two possible solutions to create a TCP server. From what I have read, CAA NetBaseSrv is more user-friendly to implement than the Syssocket variant. However, I am still struggling to actually implement this library. Foremost is my little knowledge about creating a TCP server and how to read/understand each function block, especially the outputs of some blocks and the types, e.g. server has an output CAA.Handle, but I cannot find the explanation of CAA.Handle. I tried to find a good document that can help me understand how to implement a TCP server, but I could not find it. Thank you in advance, George
Last updated: 2025-02-20

Post by tk096 on gear over gear (2 masters,1 slave) - how to do it? ^{CODESYS Forge talk (Post)}
Hi, you could calculate the position/dynamics of the slave axis yourself and use one of the function blocks SMC_FollowPosition/SMC_FollowSetValues to move the slave axis. https://content.helpme-codesys.com/en/libs/SM3_Basic/Current/SM3_Basic/POUs/Movement/Direct/SMC_FollowPosition.html https://content.helpme-codesys.com/en/libs/SM3_Basic/Current/SM3_Basic/POUs/Movement/Direct/SMC_FollowSetValues.html
Last updated: 2024-08-19

Post by ph0010421 on TCP/IP client ^{CODESYS Forge talk (Post)}
Hello Use 'Import PLCOpenXML' to bring this into your project.
Last updated: 2023-12-20

Post by boehli on canOPEN ^{CODESYS Forge talk (Post)}
Hallo, gibt einen codesys Treiber oder Unterstützung für Hilscher canOPEN Slave oder Master Karten?
Last updated: 2024-05-15

Post by boehli on canOPEN ^{CODESYS Forge talk (Post)}
Hallo, gibt einen codesys Treiber oder Unterstützung für Hilscher canOPEN Slave oder Master Karten?
Last updated: 2024-05-15

Post by dkugler on Generic EtherCAT slave ^{CODESYS Forge talk (Post)}
@xiaonyan: open new topic please!
Last updated: 2024-05-17

Post by eschwellinger on Ethercat Slave - Load PDO From Device ^{CODESYS Forge talk (Post)}
Which CODESYS Version and which EtherCAT Master version?
Last updated: 2024-10-23

Post by goki on WAGO RS485 (753-652) on a 750-362 ^{CODESYS Forge talk (Post)}
hi guys Maybe someone can help me in this case. Im working with codesys 3.5 with an PFC200 (750-8212) with a Modbus TCP conection to the 750-362. On the 750-362 i have a 4DO, 8DI and a RS485 interface card. the 4DO and 8DI cards a working fine but im strugling with the rs485 card. Does someone have a example for this?
Last updated: 2024-02-08

Post by rh-pk on v3.5 SP19 - Modbus TCP Devices - Channel Limit? ^{CODESYS Forge talk (Post)}
Hello Vincent, I don't have 75 channels but it works for me as described above without any problems. There is also a parameter MAX_MODBUS_CHANNELS in the library parameters for the IoDrvModbusTCP module. The default value there is 100. Perhaps you are reaching the limit there? The value can be adjusted accordingly. I assume that this value is not accepted in the input dialogue and therefore the 'fixed' limit value 10 is used.
Last updated: 2024-04-10

Post by winki on Modbus TCP & RTU with Control for Linux SL ^{CODESYS Forge talk (Post)}
For small project, I would like to use my industrial computer as a PLC + Industrial Computer. Like that I can save the cost of one PLC. That why I am using Codesys on Linux. With the nic it is not working. I already set the IP adress with /etc/network/interfaces. Can it comes from there ? looking to "Control Linux SL" docuemntation it should work with rtu.
Last updated: 2024-10-23

Post by stefhanyestuda on codesys 2.3 ^{CODESYS Forge talk (Post)}
estou com um PLC festo CECX-X-C1, gostaria de comunicá-lo com a ihm weintek, o clp possui o módulo ethernet e no maual fala que por conta disso deve comunicar em tcp ip, modbus e etc, mas já tentei seguir o manual e nada. Na configuração do hardware ele não me aparece o módulo de ethernet pra configurar e não consigo encontrar o pacote para codesys 2.3 contendo esse módulo, alguém poderia me ajudar?
Last updated: 2025-07-04

Post by forest on SM Drive license error ^{CODESYS Forge talk (Post)}
Hi, when it comes about license, I used INVTmatic Studio, which uses Codesys, for programming INVT plc. I bought Codesys Modbus license, it was not expensive, and then realised that INVT didn't have License Manager option (greyed out in program) which is needed for using of Codesys License. I contacted support from INVT, but developers told me that option is still not available. So depending on environment for programming Codesys, you can or not use Modbus license. Good thing about this version of Modbus TCP it works both direction. I could send commands and receive feedbacks from drive. But communication stops after 30 mins. So I used simple version of ethernet modbus which is somewhere in INVT or Condesys library (I can check tomorrow) which works only one way. I could send cmd to drive, and control it, but didn't have any feedback, like some readings back in PLC. which is bad, but at least I could start it and it didn't fail after 30 mins.
Last updated: 2024-01-10

Post by atcprojectteam on Modbus Function Code 15, writing multiple coils ^{CODESYS Forge talk (Post)}
Hi all, I am using an RSTI-EP I/O card along with the EPXMBE101 Modbus/TCP network adapter. I have a Control Standard L license. I successfully connected to the I/O card via Modbus and can read inputs without any issues. However, when I try to write to the digital output modules using function code 15, I am unable to make any changes. Here’s what I have done so far: I created a small project using Structured Text. I set up Modbus channels (as shown in the attached image) and mapped the pins. When I use cyclic mode, the connection results in an error. However, when I use the rising edge, the connection works, but I don’t see any changes on the I/O card. For the output module, I assigned one bit to high. After that, I ran CODESYS Control Win V3. (Should I be running the PLC as well?) I built the program, but I am not receiving any response from the I/O card. Could you please advise on what might be causing this issue?
Last updated: 2025-02-26

Post by atcprojectteam on Modbus Function Code 15, writing multiple coils ^{CODESYS Forge talk (Post)}
Hi all, I am using an RSTI-EP I/O card along with the EPXMBE101 Modbus/TCP network adapter. I have a Control Standard L license. I successfully connected to the I/O card via Modbus and can read inputs without any issues. However, when I try to write to the digital output modules using function code 15, I am unable to make any changes. Here’s what I have done so far: I created a small project using Structured Text. I set up Modbus channels (as shown in the attached image) and mapped the pins. When I use cyclic mode, the connection results in an error. However, when I use the rising edge, the connection works, but I don’t see any changes on the I/O card. For the output module, I assigned one bit to high. After that, I ran CODESYS Control Win V3. (Should I be running the PLC as well?) I built the program, but I am not receiving any response from the I/O card. Could you please advise on what might be causing this issue?
Last updated: 2025-02-26

Post by hassaank on CODESYS V3+ WAGO PFC200+ MODBUS RTU ^{CODESYS Forge talk (Post)}
Hi everyone, I’m new to CODESYS and Wago devices, and I’m trying to set up Modbus RTU communication. I have a Wago PFC200 (8110) and a 750-653 RS485 module, and I want to read data from an energy meter using Modbus RTU. Thanks in advance for your help!
Last updated: 2025-03-17

Using CoDeSys on Raspberry Pi to poll ModbusTCP slave data, and uplink by using LoRaWAN ATIM ACW-XB ^{CODESYS Forge talk (Thread)}
Using CoDeSys on Raspberry Pi to poll ModbusTCP slave data, and uplink by using LoRaWAN ATIM ACW-XB
Last updated: 2019-01-08

Post by fugtwad on Automation Builder V2.5 EtherCAT CM579 Master Scan for devices - >No gateway selected ^{CODESYS Forge talk (Post)}
Scan from "IP-Configuration" with PC connected to first EtherCAT slave and "EtherCAT" tick box ticked gives slave info. As does ticking the "Emergency" tickbox.
Last updated: 2024-05-20

Post by kbucsit22 on Ethercat Slave - Load PDO From Device ^{CODESYS Forge talk (Post)}
Hi All, I am using Control Win V3 x64. Anyone experiences to use Expert mode to map the Ethercat Slave device to press this Load PDO from Device, Pressed first time then nothing happens. Pressed second time then the software crashes. Best regards, Kenneth
Last updated: 2024-10-22

Post by timvh on Accessing ModbusTCP addresses from python ^{CODESYS Forge talk (Post)}
https://en.wikipedia.org/wiki/Modbus
Last updated: 2023-09-20

Post by eschwellinger on IoDrvModbusTCP_Diag not defined when using MODBUS ^{CODESYS Forge talk (Post)}
known issue hopefully solved to next version
Last updated: 2024-04-18

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