Post by artplc on 3.5 P20 hangs - no response ^{CODESYS Forge talk (Post)}
Subject: Solution: CODESYS Freezes Linked to Large Symbol Configuration (OPC UA) Hello everyone, I was experiencing the same problem as many here: CODESYS (v3.5 SP20+) freezing during compilation and download, especially on projects that use OPC UA for SCADA. The only workaround was to run Build > Clean all before every download. I believe I have found the root cause and a permanent solution. The Problem: The issue is directly related to a large Symbol Configuration. In my project, I only need about 700 tags for OPC UA, but the Symbol Configuration list was showing over 250,000 tags. This is because it automatically includes all variables from Global Variable Lists (GVLs) and other memory areas. When any static variable is changed, the IDE tries to rebuild this enormous list, causing it to freeze for several minutes. The Solution: Instead of letting CODESYS export every variable by default, you can use a pragma to tell it which variables or GVLs to exclude from the symbol export process. Place the following pragma at the top of any GVL or data structure that you do not want to be part of the symbol configuration: 1 {attribute 'symbol' := 'none'} 2 VAR_GLOBAL 3 // All variables in this GVL will now be excluded from the 4 // Symbol Configuration by default. 5 InternalVariable1 : INT; 6 InternalVariable2 : BOOL; 7 END_VAR After adding this pragma to all the GVLs that were not needed for OPC UA, the number of tags in my Symbol Configuration dropped to the correct amount. The compilation and download process is now fast again, with no freezing. This method is much more efficient than manually managing the symbol list in the editor. I hope this helps others who are facing this frustrating issue. Best regards.
Last updated: 2025-08-10

Post by full0pullpolen on Device User Logon ^{CODESYS Forge talk (Post)}
The following guide describes how you can adapt the user management for the first time in a project. It deals with the definition of a user and a group to which he belongs. Requirement: the project for which the user management is to be set up is opened. There is no adapted user configuration yet. Select Project Settings ‣ Users and Groups and then the Users tab. The user Owner is already created by default. Click on Add. ⇒ The dialog box Add User appears. Enter a login name, for example ‘Dev1’, and a password. Leave the option Activated activated. Click on OK. ⇒ On creating a group for the first time, CODESYS now requests you to authenticate yourself to perform this action. In this case, enter ‘Owner’ as the current user. Do not enter a password, just click on OK. The user Dev1 appears in the list and is automatically a member of the group 'Everyone'. Change to the tab Groups, in order to add the user to a new group. ⇒ The groups Everyone and Owner have already been created. Click on Add in order to open the dialog box Add Group. Specify at least one name for the new group, for example ‘Developers’. Activate the checkbox next to the entry User ‘Dev1’ in the field Members. Click on OK. ⇒ The group Developers now appears with has user member 'Dev1'. Switch to the Users tab. ⇒ The user Dev1 now appears as a member of the groups ‘Everyone’ and ‘Developers’.
Last updated: 2024-01-24

Post by full0pullpolen on Device User Logon ^{CODESYS Forge talk (Post)}
The following guide describes how you can adapt the user management for the first time in a project. It deals with the definition of a user and a group to which he belongs. Requirement: the project for which the user management is to be set up is opened. There is no adapted user configuration yet. Select Project Settings ‣ Users and Groups and then the Users tab. The user Owner is already created by default. Click on Add. ⇒ The dialog box Add User appears. Enter a login name, for example ‘Dev1’, and a password. Leave the option Activated activated. Click on OK. ⇒ On creating a group for the first time, CODESYS now requests you to authenticate yourself to perform this action. In this case, enter ‘Owner’ as the current user. Do not enter a password, just click on OK. The user Dev1 appears in the list and is automatically a member of the group 'Everyone'. Change to the tab Groups, in order to add the user to a new group. ⇒ The groups Everyone and Owner have already been created. Click on Add in order to open the dialog box Add Group. Specify at least one name for the new group, for example ‘Developers’. Activate the checkbox next to the entry User ‘Dev1’ in the field Members. Click on OK. ⇒ The group Developers now appears with has user member 'Dev1'. Switch to the Users tab. ⇒ The user Dev1 now appears as a member of the groups ‘Everyone’ and ‘Developers’.
Last updated: 2024-01-24

Post by full0pullpolen on Device User Logon ^{CODESYS Forge talk (Post)}
The following guide describes how you can adapt the user management for the first time in a project. It deals with the definition of a user and a group to which he belongs. Requirement: the project for which the user management is to be set up is opened. There is no adapted user configuration yet. Select Project Settings ‣ Users and Groups and then the Users tab. The user Owner is already created by default. Click on Add. ⇒ The dialog box Add User appears. Enter a login name, for example ‘Dev1’, and a password. Leave the option Activated activated. Click on OK. ⇒ On creating a group for the first time, CODESYS now requests you to authenticate yourself to perform this action. In this case, enter ‘Owner’ as the current user. Do not enter a password, just click on OK. The user Dev1 appears in the list and is automatically a member of the group 'Everyone'. Change to the tab Groups, in order to add the user to a new group. ⇒ The groups Everyone and Owner have already been created. Click on Add in order to open the dialog box Add Group. Specify at least one name for the new group, for example ‘Developers’. Activate the checkbox next to the entry User ‘Dev1’ in the field Members. Click on OK. ⇒ The group Developers now appears with has user member 'Dev1'. Switch to the Users tab. ⇒ The user Dev1 now appears as a member of the groups ‘Everyone’ and ‘Developers’.
Last updated: 2024-01-24

Post by yannickasselin on Lenze i950 Servo and WAGO PFC200 ^{CODESYS Forge talk (Post)}
I don't have time to go through the whole manual but as I said earlier, the servo drive does not support any of the modes needed for SoftMotion Light to work. If you want to use the full SoftMotion, you could use SMC_Homing function block to do the homing. This function block does not use the Homing Mode. It still uses the CSP mode and does the logic in Codesys runtime instead of in the servo drive. Read the documentation about it to see if it fits your needs. But if your controller only supports SoftMotion Light, I am afraid you will not be able to use the i950. I do a lot of motion stuff with different servo brands. Some support all the modes needed for SoftMotion Light and some don't. You really need to make sure the modes are supported before choosing a brand over another. I tend not to use brand specific controllers in order not to be limited by their supported features. I usually choose a PC (Linux or Windows) and install the Codesys runtime and licences myself. This is the most flexible way to use Codesys in my opinion. Depending on how many axes are needed in your project, a full SoftMotion license may not be more expensive than SoftMotion Light because SoftMotion is available as Application based license whereas SoftMotion Light is not. But of course, SoftMotion is harder on the CPU than SoftMotion Light.
Last updated: 2026-02-13

Post by c3po on Von SNMP auf IIoT wechseln ^{CODESYS Forge talk (Post)}
Hallo, 1. ich bin komplett NEU was Codesys angeht 2. ich muss direkt ein Retrofit machen von V2 auf V3 3. Neue Steuerung: WAGO 750-8211 PFC200. 4. das Projekt in V2 hat über SNMP daten im Netzwerk zur Verfügung gestellt, oder diese gelesen 5. das Projekt in V3 kann SNMP nur noch eingeschränkt nutzen, deswegen wurde mir vom WAGO Support nahegelegt die IIoT Lib zu verwenden. Frage: Wie mach ich das? Konkret: Ich habe die WagoAppSNMP Bibliothek installiert, damit kann ich schon mal Set und Get nutzen (hoffentlich, hab es ja noch nicht getestet, sondern nur programmiert). Ist das ein schlauer Weg, das über diese Lib zu machen? Denn: was macht der SNMP_SET_PLCDATA_WRITEAREA ? Den kann ich über die Wago Lib nicht nutzen und weiß auch nicht, was dieser Baustein konkret tut (Bild im Anhang). Es scheint mir, hier werden Daten auf ein Word im Netzwerk geschrieben? Aber geht das nicht auch einfacher? Es ist ja keine Adresse hinterlegt, wo das hin gehen soll oder? Also, ich verstehe den Baustein nicht so ganz und konnte bisher auch keine Erklärung dazu finden. Vielen Dank schon mal für eure Unterstützung, K.
Last updated: 2024-08-19

Post by hppatrick on Datenkonvertierung für ein SPS-AO-Modul ^{CODESYS Forge talk (Post)}
Hi Leute , ich bin neu hier im Forum und habe seit kurzer Zeit mein eigenes SPS-Projekt. Ich stoße hin und wieder an Probleme aber habe diese auf kurz oder lang gelöst. Nun zu meinem Problem: Als Projekt habe ich eine Kühlwassersteuerung , die einen Relativdruck einließst, und anhand desssen Werte dann einen Frequenzumrichter ansteuert. Z. Bsp. 5Bar -> FU auf 70Prozent. Ich lese in Codesys den Analogwert mit der Wago A20_750_455_020 ein. Dieser Wert wird umgerechnet mit LIN_TRAFO in 0-10 (Bar)und und wird dann über einen PID Regler geregelt. (Bibliothek UTIL). Dieser Wert wird dann wieder für die Ausgangskarte Umgerechnet (LIN_TRAFO) . Nun zu meinem Problem : Die Ausgangskarte nimmt nur einen Word Datentyp und meine Bausteine haben den REAL Datentyp. Wenn ich einen Konvertierungsbaustein nehme, Schmeist mir Codesys einen Fehler und das Programm wird geschlossen. Könnt Ihr mir helfen? Vielen Dank im Voraus (Datei habe ich angehängt). Die Ausgangskarte ist eine Wago 750-555-08
Last updated: 2024-06-14

Post by gilbert-mh on CAA net base TCP client cause PLC to crash - Kernel message : N0HZ_local_softirq_pending 80 ^{CODESYS Forge talk (Post)}
Hello all, I have been trying to implement a TCP client on a Festo PLC (CPX-E-CEC-M1) and it looks like it works well except that after some time (greatly varies between a few hours to more than 100h) my PLC crash. When I look into the log file the only thing I see is that before the crash happens a few kernel warnings : N0HZ_local_softirq_pending 80 and then the crash. I've looked into this warning and from what I could find on the net it seems that this is warning is triggered when the ethernet link is down. I've tried to correct this bug for quite some time and what I know is that : - The crash is caused by my TCP client, when I remove it from my code I see no crash - The crash happens more quickly the more the TCP client is used. - The time before the crash is not directly proportional to the number of communications or their size. But it looks like it is just more likely to happen if the client connect to the server at a higher frequency. - The precedent observation makes it seem unlikely that the crash is caused by some memory overflow because then the crash speed would be more proportional to the amount of data exchanged. SO from these observations, I believe that the crash could be caused by the PLC trying to connect to a server while there is some kind of issue with the ethernet link resulting in the PLC getting stuck in some indefinite state and making it crash. This still seems a bit unlikely to me because if the ethernet is down it simply shouldn't be able to contact the server and the communication would just fail which doesn't cause my PLC to crash. Has anyone encountered the same kind of problem (with the same kernel message) ? I am pretty sure the warning is not the direct cause of the crash but just an indicator that something is wrong with my PLC. Thanks in advance
Last updated: 2024-01-12

Post by pppn on Issue with Forward Open Connections in Ethernet/IP Protocol Stack in Codesys ^{CODESYS Forge talk (Post)}
Hello, I am facing an issue with my Ethernet-based project in Codesys. My product was functioning well until I modified the protocol stack and uploaded it to my device. Here are the details of my problem: Project Setup: I am working on an Ethernet-based project to test my product. The project was running without issues before modifying the protocol stack. Issue: After modifying the protocol stack and uploading it to my device, I am encountering an error in Codesys related to the forward open connections. Error status: connection failure, extended: connection in use or duplicate forward open. According to the Ethernet/IP protocol in codesys, there are three forward open connections that need to be established. The first two connections are opening without any issues. The third connection, which is an input-only connection, is causing problems. The error message indicates that the connection is already open. Debugging Attempts: I have extensively debugged the protocol stack and found no issues. The product works well when tested with EIP tools but not with Codesys. Exclusive owner connections are working correctly, and only the input-only connection is problematic. Wireshark Traces: Wireshark traces show that the third connection attempts to open but reports that it is already open. Steps to Reproduce: Modify the protocol stack and upload it to the device. Attempt to establish three forward open connections in Codesys. Observe the error on the third connection (input-only). Request: I would appreciate any suggestions or guidance on how to resolve this issue. If there are specific settings or configurations in Codesys that I need to check, please let me know. Additionally, if there are known issues or workarounds related to this problem, I would be grateful for the information. Attachments: Wireshark traces showing the connection attempts and errors Screenshots of the error messages in Codesys codesys version: CODESYS V3.5 SP16 Patch 3 + 64 bit
Last updated: 2024-06-25

Post by pppn on Issue with Forward Open Connections in Ethernet/IP Protocol Stack in Codesys ^{CODESYS Forge talk (Post)}
Hello, I am facing an issue with my Ethernet-based project in Codesys. My product was functioning well until I modified the protocol stack and uploaded it to my device. Here are the details of my problem: Project Setup: I am working on an Ethernet-based project to test my product. The project was running without issues before modifying the protocol stack. Issue: After modifying the protocol stack and uploading it to my device, I am encountering an error in Codesys related to the forward open connections. Error status: connection failure, extended: connection in use or duplicate forward open. According to the Ethernet/IP protocol, there are three forward open connections that need to be established. The first two connections are opening without any issues. The third connection, which is an input-only connection, is causing problems. The error message indicates that the connection is already open. Debugging Attempts: I have extensively debugged the protocol stack and found no issues. The product works well when tested with EIP tools but not with Codesys. Exclusive owner connections are working correctly, and only the input-only connection is problematic. Wireshark Traces: Wireshark traces show that the third connection attempts to open but reports that it is already open. Steps to Reproduce: Modify the protocol stack and upload it to the device. Attempt to establish three forward open connections in Codesys. Observe the error on the third connection (input-only). Request: I would appreciate any suggestions or guidance on how to resolve this issue. If there are specific settings or configurations in Codesys that I need to check, please let me know. Additionally, if there are known issues or workarounds related to this problem, I would be grateful for the information. Attachments: Wireshark traces showing the connection attempts and errors Screenshots of the error messages in Codesys codesys version: CODESYS V3.5 SP16 Patch 3 + 64 bit
Last updated: 2024-06-25

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

Post by brouwyka on JSONByteArrayWriter string result incorrect order ^{CODESYS Forge talk (Post)}
Hi @TimvH, As discussed in our email contact, your example does not actually test/reproduce the bug I am describing: Adding to the JSON builder on later cycles works fine. Your example works because you do the following: 1. You finish the first cycle (xFirst) with adding an object to the array with 2 fields; 2. When the next cycle is triggered (xAdd), you immediately start with adding another object to that array. This works fine as the last thing you did before #2 was the addition of the array and an object to it. To reproduce the bug you should be doing the following instead, as I showed with the code I shared with my first post: 1. Create the array - save the index that is returned; 2. Add an item, either a primitive or an object, to the array; 3. Add an item outside the array (anything: a primitive, a new array, a nested object, etc); 4. Add another item to the array using the index you saved at #1. You will now see, as I shared in my initial post, that the second item is placed completely outside the root JSON object. This also happens to anything else you try to add after step #4: everything after this point will be added outside the root JSON object: the JSON is completely broken. Important to note is that this not only happens with arrays, but also with nested JSON objects. Once you add something outside of a nested JSON object, you can no longer add anything to that nested JSON object, as that causes the exact same bug. This also applies to arrays of objects, so if in your test you had tried adding a new key-value pair to the first nested object in your array after you created the second nested object, you would also run into this bug. It seems that the JSONByteArrayWriter (I haven't tested the other writers in the JSON Utilities SL library, so I don't know if they suffer from the same problem) simply does not handle any JSON fields that add brackets (so arrays with "[" & "]" and nested objects with "{" & "}") well, and closes them prematurely instead of checking if any later JSONElements in the JSONData's array belong to any of these bracketed fields. After reviewing the objects & functions of the JSON Utilities SL library, my guess is that either the JSONByteArrayWriter linearly goes through the array of JSONElements in the JSONData and only checks the diParentIndex of each JSONElement in direct ascending order, OR if it does use the JSONElement.GetChildren(); method, that this method is either broken and doesn't give all children correctly to the writer. Neither explains why everything completely breaks, and you cannot even add to the root JSON object anymore, however, so there is probably more than just that going wrong in the writer. To me, after a full week of testing and attempting workarounds, this seems like a bug in the library that needs to be fixed by Codesys, as I cannot see anything wrong in the JSONData constructed by the JSONBuilder - this seems purely a problem in the writer.
Last updated: 2026-06-15

Post by rossanoparis on After un upgrade of "CODESYS Control for Raspberry Pi MC SL" from v4.7 to v4.9 SysFileOpen function stopped working ^{CODESYS Forge talk (Post)}
Hello at all. After un upgrade of "CODESYS Control for Raspberry Pi MC SL" from v4.7 to v4.9 SysFileOpen function stopped working. I'm not able to read or write files from the PLC application. Before this upgrade all worked fine. I've read this thread [ https://forge.codesys.com/forge/talk/Engineering/thread/3da9ded84e/ ] Despite I followed that indications I couldn't get my code working again. Perhaps I'm missing something or I didn't understand how to use placeholders at all. Is there a different syntax to use for "SysFileOpen" in order to use placeholders? Thanks in advance for your help. Information Compiler: CODESYS V3.5 SP19 Patch 2 Runtime: codesyscontrol 4.9.0 HW: KUNBUS RevPi Connect S Below the paths I want to access (The entire CODESYSControl_User.cfg file is attached) [SysFile] PlaceholderFilePath.1=/home/pi/hpca/bin, $hpcabin$ PlaceholderFilePath.2=/home/pi/hpca/cfg, $hpcacfg$ PlaceholderFilePath.3=/home/pi/hpca/logs, $hpcalogs$ PlaceholderFilePath.4=/home/pi/hpca/resources, $hpcares$
Last updated: 2023-08-22

Post by sturmghost on Visualization using methods and cyclic ST-calls ^{CODESYS Forge talk (Post)}
Im looking for a way to implement ST-code into the visualization element without creating a helper POU or method in my device/application tree. Like visualization properties are evaluated at each VISU_TASK cycle I want to be able to create own ST code which interacts with the visualization interface variables. To be more specific I want to have a property which executes user defined ST-code at each VISU_TASK cycle exactly like its already possible for Input Configuration on various mouse and dialog events. Also a property for initialization (so only executed once) and a timed property would be nice. With the situation right now I'll have to create a POU function which handles the ST-code and misuse a property, like the text variable, to execute this POU function at each VISU_TASK cycle. Or does it exist and I don't know it?
Last updated: 2023-10-02

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