Post by ggaida on runtime dynamic modbus devices ^{CODESYS Forge talk (Post)}
Kurtk, I am working through a very similar scenario. I am curious if you have had any success since your post in implementing dynamic modbus configurations? Thx!
Last updated: 2025-11-20

Post by tristan on Textfield display problem ^{CODESYS Forge talk (Post)}
Hello Tim, I am using CODESYS Visu V4.8.1.0. It works when I turn off the "Support client animation and overlay of native elements". But if I do that, dialog box moving and other options are also disabled so it is a bit problematic. Thank you for helping.
Last updated: 2025-11-27

Post by remlab on WebClient result empty ^{CODESYS Forge talk (Post)}
If I try http://192.168.0.250:50543/api/xdevices.json?key=XXX&SetC1=1 it write correctly Why can I write but I can't read the Json ?
Last updated: 2026-03-04

Post by bdschnapp on OPC-UA ApplicationUri / ProductUri ^{CODESYS Forge talk (Post)}
Were you able to figure out if it is possible to change the Application/Product URI of your server? I am having the same problem.
Last updated: 2026-03-16

Post by ph0010421 on Network variable stops sending ^{CODESYS Forge talk (Post)}
I'm having right now trouble if the NVL is 'big' and I've needed to reduce the size. It sends for (about) 1 hour then stops.
Last updated: 2026-04-30

Post by amira on Visu 4.9.1 auto-logon/login ^{CODESYS Forge talk (Post)}
Hello Julian, could you please check in Chrome Password Manager Settings if the option "Offer to save passwords" is set? With this option selected, a pop-up message will then show up asking whether or not to save the password. Choose OK. Hope this helps.
Last updated: 2026-01-14

Post by eschwellinger on The element of type 'VisuFbElemImage' could not be updated. Reason: Index was outside the bounds of the array. ^{CODESYS Forge talk (Post)}
check with the CODESYS Installer er if you are on latest Visuversion. 4.9.1.0
Last updated: 2026-01-27

Post by fleaplc on Modbus TCP Server connection is ESTABLISHED but all holding registers are value 0? ^{CODESYS Forge talk (Post)}
Did you check the communication with a sniffer ? (ex. Wireshark) to check if the holding get to zero by a wrong writing (client initialization?) o something else?
Last updated: 2026-01-27

Post by eschwellinger on Unable to deploy "Control for Linux SL 4.18.0.0" ^{CODESYS Forge talk (Post)}
Hi could you check if this really exists in 4.19.0.0 deploy tool? In your case architecture is missing- see my configuration
Last updated: 2026-02-17

Post by timvh on Unit testing support / libraries for EcoStruxure Machine Expert (CODESYS) ^{CODESYS Forge talk (Post)}
If the Professsional Developer Edition (which includes the Test Manager) is not supported by Schneider, then an option is to use the Open Source Unit test framework. See: https://forge.codesys.com/lib/counit/home/Home/
Last updated: 2026-02-20

Post by akneer on HMI über Webbrowser ^{CODESYS Forge talk (Post)}
Beispiel: IF bShutdownPC THEN bShutdownPC := FALSE; // LINUX SysProcess_Implementation.SysProcessExecuteCommand( pszComand:='shutdown -h 0', pResult := ADR(udiError)); // WINDOWS SysProcess_Implementation.SysProcessExecuteCommand( pszComand:='shutdown.exe -s -t 05', pResult := ADR(udiError)); END_IF
Last updated: 2026-03-04

Post by fpawlak on How to register own component - CMAddComponent() or CMAddComponent2() ^{CODESYS Forge talk (Post)}
Hi, so really oneone has no idea which way is correct one? Or maybe both are okey if they work for me?
Last updated: 2026-03-13

Post by nulltrace on How change Unity-ID in TCP Modbus Slave ^{CODESYS Forge talk (Post)}
Hey, I also waiting for feedback from Mr. Schwellinger @eschwellinger, please send me an answer, i would appreciate it. The clue is, i know the solution, but have to check if it's allowed to share.
Last updated: 2026-04-14

Post by julianramirez on Codesys Trend - setting Y axis minimum and maximum as variables - error ^{CODESYS Forge talk (Post)}
Hello Hannibal, I am using real vars and it works, however, if I update those vars in real time it doesnt quite change it on y axis, do you think it is because it is not an integer?
Last updated: 1 day ago

Post by mondinmr on COL.IMap2 and HashTableFactory cause frequent Access Violation ^{CODESYS Forge talk (Post)}
Good morning, I’ve been using the Collection library for a long time, mostly with Stack, LinkedList, and List. From your examples I was able to manage the different factories, even for custom elements. Now I need a hashtable, but with this object I’m running into a lot of random access violations. If I append something inside FB_Init after constructing the hashtable, it crashes, even though the list was already created. If I only create the hashtable in FB_Init and append afterwards, it usually works. I don’t understand the meaning of the dispose call in this code: pSlave := ADR(slave); uSlave := TO_ULINT(pSlave); iKey := fKey.Create(uSlave); IF hash.CountKeys() = 0 THEN Service.logger.appendLog('Filling hashtable', 'HashManager', AdvLogType.AdvDebugMsg); ok := FALSE; ELSE eError := hash.ContainsKey(iKey, xResult => ok); END_IF IF NOT ok THEN pI := __NEW(UINT); iVal := fKey.Create(TO_ULINT(pI)); Service.logger.appendLog(CONCAT('New slave', TO_STRING(uSlave)), 'HashManager', AdvLogType.AdvDebugMsg); hash.AddKeyValuePair(iKey, iVal); appendNewSlave := pI; ELSE eError := hash.GetElementByKey(iKey, itfValue => iElem); xResult := __QUERYINTERFACE(iKey, itfIInstance); IF xResult THEN itfIInstance.Dispose(); END_IF IF eError <> COL.COLLECTION_ERROR.NO_ERROR THEN Service.logger.appendLog(CONCAT('ERROR ', TO_STRING(eError)), 'HashManager', AdvLogType.AdvCriticalMsg); appendNewSlave := nullptr; RETURN; END_IF __QUERYINTERFACE(iElem, iVal); {warning disable C0033} pI := TO___UXINT(iVal.UlintValue); {warning restore C0033} appendNewSlave := pI; END_IF Without the dispose call, every second cold reset crashes immediately when I try to access iVal, even if eError doesn’t report any error. With the dispose call, the cold reset issue disappears, but I get other problems: a) If I start the runtime using systemctl start codesyscontrol, it crashes at IF hash.CountKeys() = 0 THEN b) If I delete the files in PlcLogic and download again, it works and survives multiple cold resets. But as soon as I run systemctl restart codesyscontrol, everything gets corrupted again and it starts crashing at that point. FUNCTION_BLOCK SlaveMapCounter VAR hash : COL.IMap2; eError : COL.COLLECTION_ERROR; END_VAR In its FB_Init I create it: METHOD FB_Init: BOOL VAR_INPUT bInitRetains: BOOL; // TRUE: retain variables are initialized (reset warm / reset cold) bInCopyCode: BOOL; // TRUE: the instance will be copied to the copy code afterward (online change) END_VAR VAR hF : COL.HashTableFactory; END_VAR hash := hF.Create(256); In another FB I instantiate it statically: FUNCTION_BLOCK ABSTRACT AbstractServoEthercatController EXTENDS AbstractServoController VAR_STAT hashSlaves : SlaveMapCounter; END_VAR VAR field : REFERENCE TO ADVAbstractFieldUnitEthercatCia402; initCnt : REFERENCE TO UINT; END_VAR The append method is the one shown above, and I call it after the runtime has started. The accesses are performed by a single task, and in any case I’m working on an isolated single core. I’ve tried everything, moving the create, the instances, and all the rest several times, but nothing seems to work. I’d like to point out that these FBs are part of our own library, which is used in many applications.
Last updated: 2025-09-11

Post by fefefede on Get the numer of day ^{CODESYS Forge talk (Post)}
Hello i tro to create a program to turn on or off the air condition in relationship temperature and numer of day. I can't get the number of day. I try this after installing SysTime library but this not work and have this error on debug ------ Build started: Application: Device.Sim.Device.Application ------- Typify code... Generate code... [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0032: Cannot convert type 'Unknown type: 'SysTimeCore(TRUE)'' to type 'TIME' [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0035: Program name, function or function block instance expected instead of 'SysTimeCore' [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0032: Cannot convert type 'Unknown type: 'DayOfWeek(CurrentTime)'' to type 'INT' [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0035: Program name, function or function block instance expected instead of 'DayOfWeek' [INFORMATION] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0181: Related position Build complete -- 4 errors, 0 warnings : No download possible PROGRAM PLC_PRG VAR Temperatura: UDINT; AriaCondizionata: BOOL := FALSE; CurrentDayOfWeek: INT; //Variabile Giorno CurrentTime: TIME; GiornoDellaSettimana: INT; DayOfWeek: INT; END_VAR CurrentTime := SysTimeCore(TRUE); // Ottieni l'ora corrente CurrentDayOfWeek := DayOfWeek(CurrentTime); CASE GiornoDellaSettimana OF 1: // Azioni per Lunedì 2: // Martedì se più 10° accend altrimenti spegni IF Temperatura >= 10 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 3: // Mercoledì se più di 50° accendi altrimenti spegni IF Temperatura >=50 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 4: // Giovedì se più di 40° accendi altrimenti spegni IF Temperatura >=40 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 5: // Venerdì se più di 50° accendi altrimenti spegni IF Temperatura >=50 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 6: // Sabato se più di 25° accendi altrimenti spegni IF Temperatura >=25 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 7: // Domenica sempre spenta AriaCondizionata := FALSE; END_CASE
Last updated: 2023-09-14

Post by jeffg on ERROR: GetNetLinkSockAndInfoByMac(): could not open netlink socket: Too many open files ^{CODESYS Forge talk (Post)}
I just installed codesys runtime on a raspberry pi Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz (Compute Module 4) I am running on Codesys control for raspberry pi 64 SL ver 4.13.0 and I keep getting a crash after about five to ten minutes. This program was running fine on a 32bit system with runtime 4.8 previously but they upgraded the panel PC cause it got smashed. Looking at the logs I see this error "ERROR: GetNetLinkSockAndInfoByMac(): could not open netlink socket: Too many open files" at the time of crash. I do have a UDP socket open for a serial to ethernet adapter and im wondering if maybe its opening a bunch of sockets and while receiving messages, Im not sending anything to the device only receiving. Below is the code used for the UDP VAR // Scale Comm fbPeerServer : NBS.UDP_Peer; ipAddress : NBS.IPv4Address; fbReceive : NBS.UDP_Receive; xPeerActiv : BOOL := TRUE; abyReceive : ARRAY [0..255] OF BYTE; sLastValidReceive : STRING(255); udiIndex : UDINT; END_VAR IF xPeerActiv AND NOT fbPeerServer.xBusy THEN ipAddress.SetInitialValue(ipAddress := gvlSettings.sIPAddres); fbPeerServer(xEnable := TRUE, itfIPAddress := ipAddress, uiPort := gvlSettings.uiPort); END_IF fbPeerServer(); fbReceive(xEnable := fbPeerServer.xBusy, itfPeer := fbPeerServer, pData := ADR(abyReceive), udiSize := SIZEOF(abyReceive)); IF fbReceive.udiCount > 0 THEN IF fbReceive.udiCount < SIZEOF(sLastValidReceive) THEN SysMem.SysMemCpy(pDest := ADR(sLastValidReceive), pSrc := ADR(abyReceive), udiCount := fbReceive.udiCount); // Set End of String sLastValidReceive[fbReceive.udiCount] := 0; END_IF END_IF If anyone as seen this I could really use some help figuring it out. I included the Log report
Last updated: 2024-09-19

Post by yannickasselin on MQTT QoS 1 & 2 ^{CODESYS Forge talk (Post)}
Hello, After some more tests, here is what I found out. It seems we have to increase the uiKeepAlive and tPingInterval parameters. If I increase the uiKeepAlive value to 60s and the tPingInterval to 30s, then if I disconnect the ethernet cable from Codesys and publish some messages to which Codesys subscribes to and then reconnect within 30s, I will get the messages. If I don't reconnect the cable within 30s (ping interval), the client goes in error with "ACKNOWLEDGE_TIMEOUT". When this happens, it will not automatically reconnect after reconnecting the cable. I have to disable and re-enable the client but I will not get the published messages. I need to do more tests because there are a lot of weird things happening when playing with the ping interval and the keep alive. It is not clear to me what does what. I even ended up not receiving messages anymore, even if I disabled and re-enabled the mqtt client. The client did not give any error. The only way I was able to get messages again was by modifying my client ID. After that, if I try to re-use one of the old client IDs, nothing works (publish, subscribe) and I get a TCP_INIT_ERROR and sometimes a TCP_READ_ERROR. I need more explanation/documentation about these weird behaviors. Maybe it is the way I use it, maybe it is related to the broker (I am using Mosquitto with default parameters). When using a Node-Red client, everything works perfectly. I am trying to achieve the same behavior with Codesys but it seems impossible so far.
Last updated: 2024-10-30

Post by duvanmoreno24 on Modbus writing on value change ^{CODESYS Forge talk (Post)}
Hi all, I want to know if someone has an idea of how I can write on value change in Modbus Codesys. I have a Wago PLC and I was used to work with E-cockpit which it was quite easy to do that without the necessity to trigger any value when there was a change in the variable ( I will put how easy is ). how you can see just changing the trigger in "On value Change" will do that channel writing automatically when It detects a change in those arrays. On the other hand, in Codesys if I enable the rising edge in Codesys It ask me to put a bool variable and if triggers is going to write that value. That is making me that I have to create a function or a logic to detect the change, the problem I have is that doing that is very tedious. I first approach I got it was to create a Function who returns a bool when the value change, but I tried to keep the old value but what is happening is that in Functions all the data is erased every cycle so I can not keep any Old value. so in the Main program the trigger is going to be TRUE all the time due, the old value is cero every cycle. The second approach I got it was using a function Block (POU_1) and it works but I dont want to instance that function for every Channel or value that I want to check if the value change, Basically if I have 200 values to write trhough modbus I have to create 200 instances of that function which I think it is not practicall at all. It should be a better way to implement this as e-Cockpit from Wago Does. However, I haven't been able to know how.
Last updated: 2024-03-26

Post by mondinmr on Frustration-Fueled Feedback on Project File Management and Git Integration ^{CODESYS Forge talk (Post)}
In reality, other vendors are already moving towards integration with VS Code. B&R, for example, is likely the only one that could truly challenge Codesys in the market: they’ve overhauled their once-archaic environment (previously lacking ST OOP) and are now catching up significantly with Automation Studio Code, offering modern programming capabilities and native support for tools like Git and GitHub Copilot. The other big names in the market, frankly, are still light years behind. For smaller projects, typically handled by “wire strippers” (with all due respect!), a classic environment might be just fine. But once you’re dealing with thousands or even millions of lines of code—possibly organized in an OOP paradigm, spanning large teams, integrating third-party libraries, requiring version control, and performing comprehensive tests—a lightweight, responsive editor supercharged with AI-based features becomes essential. The real strength of something like VS Code lies in its vast ecosystem of extensions and integrations: from advanced Git support to automated build/test pipelines, and even AI-assisted autocompletion that already makes software development much more agile and productive. I understand that a PLC project involves more than just ST code (task setup, fieldbus configuration, libraries, etc.). However, there’s no technical reason not to at least provide ST files in a pure text format, making version control and collaboration far easier. B&R has clearly adopted this approach; I hope Codesys will accelerate its own efforts to offer a native, text-based integration and modern development tooling. Once you go beyond a certain level of complexity—dozens of configurations, OOP hierarchies, and distributed teams—you really do need “engineer-level” software tools, not just solutions targeting “wire strippers.” For large-scale automation projects, a more open and flexible approach is the only way to avoid chronic frustration. Let me emphasize that I truly love Codesys and consider the work done so far to be brilliant—I’d be sorry to see it overshadowed by others moving faster in this direction.
Last updated: 2025-02-18

Post by pernockham on Slider instance value when accessed through "execute ST-code" ^{CODESYS Forge talk (Post)}
I have a time which I want to modify with a slider. I have confirmed it is possible to set the value of the slider by to_real(time) (I can see that the slider changes according to 'my_time_value's value). Slider variable: to_real(my_time_value); However I fail to access the current slider instance value when I want to write back the value as time (write to a variable will not work as I need a type-conversion before assignment). my_time_value := to_time(slider-instance-value); I tried with this^.? but could not see anything interesting and also THIS^.GEN_Instance.? but nothing resemble what could be the sliders value. Anyone that knows? Thanks!
Last updated: 2025-02-06

Post by ouzago on ERROR C0138: No matching 'FB_Init' method found for instantiation of VisuClientObjectMgr ^{CODESYS Forge talk (Post)}
When I created a new project in CODESYS using the "Standard Project" template and then added a Visualization, I was receiving the C0138 error during compilation. This issue persisted even with a new, completely empty project. A Quick and Effective Solution (My Method): After many attempts, I solved the problem as follows: From the File -> New Project menu, I selected the "HMI Project" template directly, instead of the "Standard Project" template. After creating the project with this template, I added my POUs, Tasks, and programs (e.g., Ladder, ST). Using this method, the project compiled successfully without any errors. So, my question is: are there any other solutions besides this method?
Last updated: 2025-10-07

Post by dhumphries on Toggling Visualizations using HMI Physical Buttons ^{CODESYS Forge talk (Post)}
Nothing wrong with ladder, in a lot of applications it is simpler than ST or CFC, you're a lot less likely to have syntax issues in a ladder diagram than in structured text as long as you stick with traditional ladder elements. Your attempt was almost valid, but you tried to change the currentvisu variable using a blend of structured text and ladder, which isn't allowed. You need to use the MOVE operator and define the visualization name as a string on the input side and the visuelems.currentvisu as the target on the output side.
Last updated: 2024-02-28

Post by esave on Stepper Drive with Ethercat ^{CODESYS Forge talk (Post)}
Hello everybody I am new into Codesys. I have a stepper driver (EM3E-556E) from Leadshine. I want to controll the stepper driver via EtherCat to a ST programm but I dont have any function block or anything that i can use. I only have the XML-File wich I loaded. With it I implemented the drive as a Ethercat slave and now I see these variables. (See picture) I dont know how to controll the stepper drive. And the manufacturer doesnt provide support for me. Can anybody help me or atleast tell me how they would do it?
Last updated: 2024-03-14

Post by k2saki on CNC Open Source Project / Can I convert my project to text-files ? ^{CODESYS Forge talk (Post)}
Hi. I published My CODESYS-CNC Project to GitHub and I set it Open Source Software. Here https://github.com/k-s-saki/RPi_CODESYS_CNC My CNC Project is binary file , using FBD for IPO , so I found it is a little bit hard to work with people on GitHub. (diff / merge ) My question is 1) Is it possible to convert my project ( only POUs is also fine ) into text file ? How? 2) Would it be better to rewrite all FBD/LD into ST and copy them manually to text files? Thanks.
Last updated: 2024-05-16

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