Post by hagroth on v3.5 SP19 - Modbus TCP Devices - Channel Limit? ^{CODESYS Forge talk (Post)}
Today I was struggling with the same problem. in search for a solution i found this thread. Then i tried some things. It doesn't seem to be just a libraries' fault. In addition to 3.5.19, we also have a 3.5.18 version installed, the library versions of Modbus_TCP_Master and Modbus_TCP_Slave are the same, but more than 10 slave channels can be added in 3.5.18
Last updated: 2024-02-02

Post by rd76065 on Opto 22 Groov PR2 Modbus TCP Master communication ^{CODESYS Forge talk (Post)}
Previously, I have used ModbusEthernet_04 library for Wago for ModbusTCP Master communicational in Codesys V2.3. How to use same communication of similar UDT for Opto22 Groov PR2 PLC in Codesys V3.5 SP20. Can I use OSCAT library - Network -MB_Client or IODrvModbusTCP - ModbusRequest for this requirement? If any other please guide.
Last updated: 2024-05-31

Post by kislov on Change modbus server parameters from program ^{CODESYS Forge talk (Post)}
Use in IEC-code: Modbus_Serial_Device.UpdateComPortSettings(...) https://content.helpme-codesys.com/en/libs/IoDrvModbusSerialSlave/Current/pou-ModbusSerialDeviceDiag/UpdateComPortSettings.html Take note: "Only possible if server is disabled (see xEnable Input)" So: Modbus_Serial_Device.xEnable := FALSE; Modbus_Serial_Device.UpdateComPortSettings(...) Modbus_Serial_Device.xEnable := TRUE; Please note that after PLC reboot the values from the GUI (from your screenshot) will be applied again. So you need to save values from HMI in RETAIN and restore them after start of application.
Last updated: 2024-07-17

Post by mavitia on Application based license problem - Modbus TCP ^{CODESYS Forge talk (Post)}
I am running ubuntu on a raspberry pi, and installed an application based license Control Basic M on it, it runs a demo program fine, does not timeout etc. however, when I add a modbus TCP device, I start getting errors: <Entry severity="error" component="CmpApp" user="nobody" timestamp="12/18/2023 3:49:42 PM" infoId="24">Online change denied. Application Application is in exception state!</Entry> <Entry severity="error" component="CmpApp" user="nobody" timestamp="12/18/2023 3:49:42 PM" infoId="68">Download failed: Application=Application</Entry> <Entry severity="exception" component="CmpApp" user="nobody" timestamp="12/18/2023 3:49:41 PM" infoId="0">Application app=Application has invalid license metrics!</Entry> the modbus tcp slave runs, and the counter ticks up, however, when I call the variables on the %IX0.0 in my program, and try to upload the changes, I am getting the error messages which stop the program as far as I understand, the application based, M includes 2 fieldbus instances, but on the other side is fairly new, anything obvious I am missing out here?
Last updated: 2023-12-18

Post by alexgooi on Modbus TCP interface get stuck ^{CODESYS Forge talk (Post)}
Dear Forum, I'm currently experimenting with Modbus interfaces in combination with a virtual controller. I have the following setup (Modbus_Setup.png): I have an IPC with Debian installed on it (Debian 13). On this Debian machine I have installed a docker server and on this docker server a Codesys runtime container is deployed (Codesys_image.png). The Modbus scanner makes connection with and IO coupler and this works well. But when I physically disconnect the ethernet connection between the IPC and the IO coupler the Modbus interface gets stuck in a state where it gets stuck in the busy state (Modbus_Stuck.png). When I plug the cable back in, the IO coupler isn't communicating until the xBusy variable is manually set to False, after this action is performed the communication goes back to normal. I have tried to set the container network to host and bridge (Network.png), but both version gives the same result (stuck scanner). I would expect that the Modbus interface is generating a timeout after 1 sec, because this is how it is setup (Modbus_settings.png), but this is not what happens. I have thought to write a piece of code that writes xBusy to false when it is stuck but because it is an output I'm not able to write to it. I have tried this with another PC (different CPU/motherboard) but this gives the same outcome. I tried updating to the latest version of Virtual control (4.20) but this gives the same result. I also tried to do the same thing with an ethernet IP scanner, and this gives an error after the timeout is expired (so this works well). I have tried to connect to the IO coupler using the Modbus_FB lib (Modbus_FB.png) the FB's are giving the correct errors and behaving as expected. At last I have tried to use a Scanner on a Codesys controller (no IPC) and here the scanner behaves as expected (an alarm is triggered after the timeout has been expired). The version of the Codesys components are listed in the picture Versions.png Is there anyone that can give me a push in the right direction? Kind regards Alex
Last updated: 2026-04-14

Global variable access by Programms and Modbus Devices (attach device to bus) ^{CODESYS Forge talk (Thread)}
Global variable access by Programms and Modbus Devices (attach device to bus)
Last updated: 2024-07-18

Timeout Error in Modbus Communication with WAGO PFC200 and iEM2050 Meter using 750-652 Module ^{CODESYS Forge talk (Thread)}
Timeout Error in Modbus Communication with WAGO PFC200 and iEM2050 Meter using 750-652 Module
Last updated: 2024-07-30

Connecting to SoftPLC Only Works By Turning Off Modbus Ethernet Port ^{CODESYS Forge talk (Thread)}
Connecting to SoftPLC Only Works By Turning Off Modbus Ethernet Port
Last updated: 2024-08-08

OPTO22 Groov Epic PR2 Modbus Comms Dropping out every 2 hours and 4 Mins ^{CODESYS Forge talk (Thread)}
OPTO22 Groov Epic PR2 Modbus Comms Dropping out every 2 hours and 4 Mins
Last updated: 2024-09-11

Post by kislov on CODESYS Modbus 4.4.0.0 - Modbus network redundancy ^{CODESYS Forge talk (Post)}
Solved. Enable this feature by editing C:\ProgramData\CODESYS\Devices\89\0000 0005\4.4.0.0\device.xml (config params 9105 and 9106).
Last updated: 2024-10-08

Modbus: Is there a way to get the channel index from the channel name? ^{CODESYS Forge talk (Thread)}
Modbus: Is there a way to get the channel index from the channel name?
Last updated: 2024-10-21

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

Dynamically enabling/disabling Modbus slave devices in runtime (performance issue with timeouts) ^{CODESYS Forge talk (Thread)}
Dynamically enabling/disabling Modbus slave devices in runtime (performance issue with timeouts)
Last updated: 2025-08-13

Need help to figure out Running an AC motor with modbus RTU ^{CODESYS Forge talk (Thread)}
Need help to figure out Running an AC motor with modbus RTU
Last updated: 2021-02-03

Enable more than one COM port in raspberry for more modbus channels with USB ^{CODESYS Forge talk (Thread)}
Enable more than one COM port in raspberry for more modbus channels with USB
Last updated: 2020-02-07

RTS signals are misaligned to Modbus COM port packets when using the RaspberryPi ^{CODESYS Forge talk (Thread)}
RTS signals are misaligned to Modbus COM port packets when using the RaspberryPi
Last updated: 2022-09-05

Is it possible to send a real value close to 0 through modbus? ^{CODESYS Forge talk (Thread)}
Is it possible to send a real value close to 0 through modbus?
Last updated: 2023-02-25

PM564 ETH for reading data from modbus serial slave using COM1 port ^{CODESYS Forge talk (Thread)}
PM564 ETH for reading data from modbus serial slave using COM1 port
Last updated: 2017-11-28

Hallo, hat hier schon mal jemand einen Siemens V20 Frequenzumrichter in Codesys mit Modbus RTU gesteuert? ^{CODESYS Forge talk (Thread)}
Hallo, hat hier schon mal jemand einen Siemens V20 Frequenzumrichter in Codesys mit Modbus RTU gesteuert?
Last updated: 2022-12-22

Hallo, hat hier schon mal jemand einen Siemens V20 Frequenzumrichter in Codesys mit Modbus RTU gesteuert? ^{CODESYS Forge talk (Thread)}
Hallo, hat hier schon mal jemand einen Siemens V20 Frequenzumrichter in Codesys mit Modbus RTU gesteuert?
Last updated: 2022-12-22

How can I convert a 2 word modbus address to real? ^{CODESYS Forge talk (Thread)}
How can I convert a 2 word modbus address to real?
Last updated: 2014-11-22

How do you change the 'read offset' of a Modbus channel on the fly? ^{CODESYS Forge talk (Thread)}
How do you change the 'read offset' of a Modbus channel on the fly?
Last updated: 2021-04-14

How to read the status of one Modbus Slave in the codesys program ^{CODESYS Forge talk (Thread)}
How to read the status of one Modbus Slave in the codesys program
Last updated: 2021-08-15

Write float value in modbus register and Read value whit comma from codesys ^{CODESYS Forge talk (Thread)}
Write float value in modbus register and Read value whit comma from codesys
Last updated: 2018-05-28

What is the equivalent in codesys of Modbus M flag? ^{CODESYS Forge talk (Thread)}
What is the equivalent in codesys of Modbus M flag?
Last updated: 2011-12-02

Sort by relevance or date