Post by chris--o on ModbusTCP RaspberryPi zu Fronius Wechselrichter ^{CODESYS Forge talk (Post)}
Hallo zusammen, ich hab ein kleines Problem bei einer Modbus TCP-Verbindung von meinem RaspberryPi (ML) zu einem Fronius Wechselrichter. Ich habe mir die CodeSys Version 3.5SP20 heruntergeladen und die Runtime auf dem RaspberryPi mit aktualisiert. Gerät ist ein Fronius Symo 6.0-3-M Folgende Konfiguration habe ich im Wechselrichter (Siehe Bilder). Laut Registertabelle fangen die Daten bei Adresse 40001 an und gehen im Modus int+SF bis 40120 Ich habe mir also im Ethernet-Adapter einen Modubus Master und darunter einen ModbusSlave angelegt. Der Slave (Fronius) hat bei mir die IP 192.168.2.46 dazu UnitID und Port. Ich habe dann einen Kanal mit den 120 WORDS und dem OFFSET angelegt. Wenn ich nun die Konfiguration übertrage , scheint erst mal alles zu passen.. aber es flackert immer wieder ein Fehler beim Slave auf (kann nicht erkennen welcher und finde auch keine Diagnose). Es werden auch keine Daten übertragen. Alles bleibt auf 0. Ich muss dazu sagen, dass ich noch eine weiter Modbus TCP Verbindung zu einer anderen SPS habe. Die funktioniert wunderbar. Normalerweise sollten ja auch mehrere Verbindungen gleichzeitig möglich sein oder? Wäre top, wenn ihr mir helfen könntet, den Fehler zu finden. LG Chris
Last updated: 2025-06-30

Post by testlogic on Sending Sequential Modbus TCP Packets ^{CODESYS Forge talk (Post)}
I have a Modbus TCP slave device where I need to do sequential writes to the same register. The register I'm writing to is kind of like a command line, each packet is a command word encoded in Hexadecimal. I am having difficulty implementing this system in CoDeSys 3.5 SP19. I feel like the structure of the program should be something along the lines of (Pseudocode): ModbusTCPSend(Command Register, Command1) ModbusTCPSend(Command Register, Command2) ModbusTCPSend(Command Register, Command3) I have tried to implement this with a rising edge trigger wMot1OPCode := 16#E1; //Stop Motor & Kill Program xMot1SendOP := TRUE; //Send OP on rising edge xMot1SendOP := FALSE; //Reset wMot1OPCode := 16#9E; //Disable Motor xMot1SendOP :=TRUE; //Send OP on rising edge xMot1SendOP := FALSE; //Reset Where "wMot1OPCode" is the IO map for writing to the command register, and "xMot1SendOP" is the rising edge trigger for that modbus channel. However, this doesn't work. The device never responds to the modbus commands. It seems like the trigger variable is switched too quickly for modbus to send the packet. I know the modbus register is working, because I can set the channel to cyclic and the device will respond. However, I can't use this reliably because I need each command to be sent once, in order. Cyclic keeps re-sending the commands and seems like it could miss a command as well if one was sent in-between cycle time. I have also trying using the Application trigger as described by https://faq.codesys.com/pages/viewpage.action?pageId=24510480, but this is also not working for me. See attached picture for my FBD code. This seems like a simple function, I can't tell what I'm doing wrong here. Thanks for the help.
Last updated: 2024-03-06

Post by lsislsis on SIGABRT Error ^{CODESYS Forge talk (Post)}
After many tests i see that problem comes when serial communication established for modbus rtu. If the slave device not connected we don't see the exception. If the slave device connected at serial port then we have exception about 1 hour after startup and every 10 or 15 minutes. Any suggestion?
Last updated: 2024-11-08

Post by jmauer on Codesys 3.5 SP16 Modbus change port settings. ^{CODESYS Forge talk (Post)}
Hello, I'm coming to you today because I'm trying to make the baudrate and the slave number dynamic. I've tried the "updateComPortSettings" method on the slave device but it doesn't work and gives the "Modbus_COM_Port" an error. Can you tell me how you got this method to work? Thanks in advance for your help jérémy
Last updated: 2024-02-20

Post by winki on Modbus TCP Client ^{CODESYS Forge talk (Post)}
Hello, I am new on CODESYS env. I would like to do some Modbus TCP, but I am wondering If using codesys you must use the device "Modbus_TCP_Client" & "Modbus_TCP_Server". I would like to do it without device, only using ST. Is that possible ? I try the example : MODBUS_master_example, but it is not working. If it is possible to dot it without any Device I will show my code. Thx a lot
Last updated: 2024-10-25

Post by gabrielarffa on Modbus TCP/IP having problems with global variables ^{CODESYS Forge talk (Post)}
I'm using Modbus TCP/IP to communicate Codesys with Elipse E3 as the master for a college project. I have made a list of global variables to organize the programming in two different POUs. The problem is, when I try to do the mapping of variables, the program informs me of an error due to the identifiers having a "." on their names. Do I have to reorganize my code to make it an unified block or is there a way to declare their names without changing all the code structure?
Last updated: 2025-05-20

Post by gabrielarffa on Modbus TCP/IP having problems with global variables ^{CODESYS Forge talk (Post)}
I'm using Modbus TCP/IP to communicate Codesys with Elipse E3 as the master for a college project. I have made a list of global variables to organize the programming in two different POUs. The problem is, when I try to do the mapping of variables, the program informs me of an error due to the identifiers having a "." on their names. Do I have to reorganize my code to make it an unified block or is there a way to declare their names without changing all the code structure?
Last updated: 2025-05-20

Post by oymyakon on Modbus Lockup ^{CODESYS Forge talk (Post)}
Hi i have a project where i am communicating with many modbus devices using TCP to serial. This is all working extremely well except when i turn one of the remote devices off. If i leave the auto reconnect on it still doesn't talk to the rmianing devices and if i turn Auto reconnect off it locks up. Any help would be appreciated. Paul.
Last updated: 2024-08-07

Post by oymyakon on Modbus Lockup ^{CODESYS Forge talk (Post)}
Hi i have a project where i am communicating with many modbus devices using TCP to serial. This is all working extremely well except when i turn one of the remote devices off. If i leave the auto reconnect on it still doesn't talk to the rmianing devices and if i turn Auto reconnect off it locks up. Any help would be appreciated. Paul.
Last updated: 2024-08-07

Post by ahuckphin on Issues with Modbus Slave with Raspberry Pi ^{CODESYS Forge talk (Post)}
codesyscontrol_user.cfg [SysCom] Linux.Devicefile.1 = /dev/ttyUSB0 portnum:=COM.SysCom.SYS_COMPORT1; **parameters are used in the python-script ** method: "rtu" port: "COM8" baudrate: 9600 stopbits: 1 bytesize: 8 parity: 'N' timeout: 1 register address for humidity: 0x000 register address for temperature: 0x001 unit ID: 1 **parameteized in the modbus-master-comport ** see attached files
Last updated: 2024-07-11

Post by timvh on Modbus Extended Registers ^{CODESYS Forge talk (Post)}
Maybe the following helps: https://forge.codesys.com/prj/codesys-example/modbus/home/Home/
Last updated: 2023-08-26

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