Post by winki on Error in licence activation ^{CODESYS Forge talk (Post)}
Hello, Despite receiving an activation message after entering the license number, I don’t have any license installed on my gateway. I went to check in /var/opt/codesys/ and there is no License file. I searched the entire gateway for a .lic file and found no license. I’m really stuck—how can I fix this, please? When I am using the licence tools I got this picture: But nothing that have been activated. Loic,
Last updated: 2026-02-03

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 timvh on HTML5 visualization controls disabled on CODESYS Control for Linux SL - overlay not supported? ^{CODESYS Forge talk (Post)}
I would suggest to install the latest visualization and visualization add-ons. Go to Tools - CODESYS installer to updates these add-ons (or just start the CODESYS installer through the Windows start menu). After installation, restart CODESYS SP22 and update the project to use this new visualization profile (you can update this through the menu Project - Project Environment - Visualization Profile).
Last updated: 2026-08-05

Post by dmb-fan on Attemp Convert old V2.3 projects : Error HRESULT: 0x80010105 (RPC_E_SERVERFAULT)) ^{CODESYS Forge talk (Post)}
I had runnig this already. Then I updated to SP22 patch3. After that I got always this error: ===== Project importieren: XXXXnameYYYYYY ===== *[FATALER FEHLER] Fehler beim Import des Projekts: Ausnahmefehler des Servers. * [FATAL ERROR] Error importing the project: Server exception. (Exception to HRESULT: 0x80010105 (RPC_E_SERVERFAULT)) I delete the version and installed again. Same. I uninstalled all CoDeSys on the PC and installed the old SP22 patch2 new. Same error by opening old projects. Immediatly, not by converting. Convert V3.5.17 was always installed. What is happening or what can I do?
Last updated: 2026-08-11

Post by ryusoup on JSONByteArrayWriter problem? ^{CODESYS Forge talk (Post)}
Hello, I am trying to implement a FB to make JSON formatted WSTRING type message using JSON Utilities 1.9.0.0 included in the IIoT library. In my case, I want to set some objects or arrays and set values to them later. But when I wrote as the sample below, // init builder builder(pJsonData:=pJsonData, diRootObj=>diRootObj); // set the 1st key to root diKey1 := builder.SetKeyWithArray(wsKey:="key1", diParentIndex:=diRootObj, eError=>eError); // set a value to the 1st key wsValue:="value01"; builder.SetValue(Value:=wsValue, diParentIndex:=diKey1, eError=>eError); // set the 2nd key to root diKey2 := builder.SetKeyWithArray(wsKey:="key2", diParentIndex:=diRootObj, eError=>eError); // set a value to the 2nd key wsValue:="value02"; builder.SetValue(Value:=wsValue, diParentIndex:=diKey2, eError=>eError); // set a value to the 1st key again wsValue:="value03"; builder.SetValue(Value:=wsValue, diParentIndex:=diKey1, eError=>eError); // set a value to the 2nd key again wsValue:="value04"; builder.SetValue(Value:=wsValue, diParentIndex:=diKey2, eError=>eError); // write build result writer(xExecute:=TRUE, pwData:=ADR(wsResult), udiSize:=SIZEOF(wsResult), xAsyncMode:=FALSE, jsonData:=pJsonData^); the result was: { "key1": ["value01"], "key2": ["value02", "value03", "value04"] } while my expection was: { "key1": ["value01", "value03"], "key2": ["value02", "value04"] } Inspecting pJsonData^, JSONData itself seems to be ok, so I believe the issue is something caused by the writer FB. Does anyone know how to fix it? Thanks,
Last updated: 2023-10-04

Post by biiebs on Aufbau von Ablaufsteuerungen ermitteln ^{CODESYS Forge talk (Post)}
Hallo Zusammen, gibt es in CODESYS bei Ablaufsteuerungen weitere Möglichkeiten außer den AS-Einstellungen z.B. die Aufbaustruktur der Ablaufsteuerung herauszufinden? Gesamtanzahl der verwendeten Aktionen / Schritte - Im besten Fall auch die einzelnen Verzweigungen? Ich würde den gesamten Aufbau der Schrittkette gerne als "View" in einer übergeordneten Software abbilden lassen, da sich die Ablaufsteuerungen, je nach Projekt im Aufbau unterscheiden bräuchte ich die Kenntniss über den Aufbau dieser Schrittketten. Oder müsste ich mir hier einen "Workaround" programmieren, der z.B. bei Init erstmal den Aufbau der Ablaufsteuerung durchläuft und mir die nötigen Informationen liefert? Natürlich wäre auch ein Weg den Aufbau des AS-Bausteins über die PLCopen XML zu exportieren, jedoch müsste dies bei Änderungen jeweils nachgezogen werden - was etwas unschön wäre, falls dies vergessen würde. Mittlerweile habe ich auch das Tool "SFC Visu Generator" gefunden, dessen Funktion im Prinzip genau das darstellt, was ich benötige - jedoch leider nur als CODESYS interne Visualisierung. Ich würde den Export des Bausteins gerne in meine übergeordnete Software implementieren. Gibt es hier die Möglichkeit das Vorgehen zu Erfahren oder den vom Baustein generierten Export bei mir zu implementieren? Hat hier jemand sowas ähnliches schonmal gelöst? Vielen Dank im Voraus Mit freundlichen Grüßen Biiebs
Last updated: 2024-07-25

Post by blitz on Can't get SMC_SmoothPath to work ^{CODESYS Forge talk (Post)}
This code works well: PROGRAM PLC_PRG VAR execute : BOOL; abort : BOOL; doMDI : BOOL; manualDataInput : STRING(1024) := 'N5 G01 X0.00 Y200.00 N6 G01 X200.00 Y200.00 N7 G01 X200.00 Y0.00 N8 G01 X0.00 Y0.00'; stringStreamArray: ARRAY[0..NUMBER_OF_CHAINS-1] OF SMC_StringStream2 ; i : UDINT; readNCFromStream : SMC_ReadNCFromStream; sentencesFromStringSteam : SMC_GSentenceQueue ; interpreter : SMC_NCInterpreter; interpreterGeoInfoBuffer: ARRAY[1..GEO_INFO_BUFFERS_SIZE] OF SMC_GeoInfo; roundPath : SMC_RoundPath; roundPathGeoInfoBuffer: ARRAY[1..GEO_INFO_BUFFERS_SIZE] OF SMC_GeoInfo; END_VAR VAR CONSTANT MDI_FILE_NAME : STRING := 'MDI.nc'; NUMBER_OF_CHAINS : UDINT := 15; GEO_INFO_BUFFERS_SIZE : DINT := 500; END_VAR readNCFromStream.bExecute := interpreter.bExecute := roundPath.bExecute := execute; readNCFromStream.bAbort := interpreter.bAbort := roundPath.bAbort := abort; IF doMDI THEN stringStreamArray[0].Init(MDI_FILE_NAME); stringStreamArray[0].AppendData(manualDataInput); stringStreamArray[0].SetEndOfData(); i := 0 ; WHILE i < NUMBER_OF_CHAINS DO readNCFromStream.aStream[i] := stringStreamArray[i]; i := i + 1 ; END_WHILE readNCFromStream.bExecute := TRUE; IF readNCFromStream.bBusy THEN ; END_IF END_IF readNCFromStream( fDefaultVel := 10, fDefaultAccel := 10, fDefaultDecel := 10, fDefaultVelFF := 10, fDefaultAccelFF := 10, fDefaultDecelFF := 10, sentences := sentencesFromStringSteam ); interpreter( sentences:= sentencesFromStringSteam, nSizeOutQueue:= SIZEOF(interpreterGeoInfoBuffer), pbyBufferOutQueue:= ADR(interpreterGeoInfoBuffer)); roundPath( poqDataIn := interpreter.poqDataOut, dRadius := , dAngleTol := , nSizeOutQueue := SIZEOF(roundPathGeoInfoBuffer), pbyBufferOutQueue := ADR(roundPathGeoInfoBuffer));
Last updated: 2026-01-09

Post by baltzer on ICertificateVerifier.VerifyCertificate doesn't appear to override an ERR_CERT_HAS_EXPIRED rejection in TCP_Client.Upgrade() ^{CODESYS Forge talk (Post)}
Setup: Net Base Services (NBS), TCP_Client + TLSContext, ePurpose := CLIENT_SIDE, connecting to a third-party embedded device (Velux KLF200 home automation gateway) whose factory-installed TLS certificate expired on 2026-07-12 and has no user-facing renewal path. Tested on both CODESYS Control for Raspberry Pi SL (3.5.19.0) and CODESYS Control Win V3 x64, with identical results on both. Goal: Accept the peer's expired certificate via a custom ICertificateVerifier implementation, since the certificate itself can never be replaced. Implementation: FUNCTION_BLOCK FB_MyCertVerifier IMPLEMENTS NBS.ICertificateVerifier VAR udiCallCount : UDINT; aeCurStateLog : ARRAY[0..9] OF NBS.RTS_IEC_RESULT; END_VAR METHOD VerifyCertificate : UDINT VAR_INPUT hCert : NBS.RTS_IEC_HANDLE; eCurState : NBS.RTS_IEC_RESULT; END_VAR IF udiCallCount < 10 THEN aeCurStateLog[udiCallCount] := eCurState; END_IF udiCallCount := udiCallCount + 1; VerifyCertificate := 0; // also tried: VerifyCertificate := eCurState; Wired in via tlsContext.itfCertVerifer := certVerifier at declaration time, alongside itfTLSContext := tlsContext set at TCP_Client's own declaration (per an earlier forum thread here on ensuring inline start-values on FB-typed variables are actually honored when nested one level deep - that fix was needed and worked correctly for getting the handshake to start at all). Observed: - VerifyCertificate is confirmed called exactly once per connection attempt (via the call counter above). - eCurState passed in = 0x709 = ERR_CERT_HAS_EXPIRED - correctly reflecting the actual state of the peer's certificate. - Packet capture confirms the full TLS 1.2 handshake completes correctly at the wire level: ClientHello -> ServerHello -> Certificate -> ServerKeyExchange -> ServerHelloDone -> our ClientKeyExchange/ChangeCipherSpec/Finished -> server's ChangeCipherSpec/Finished. Both sides successfully complete the cryptographic handshake. - Despite this, TCP_Client.Upgrade() subsequently returns NBS.ERROR.CONNECTION_ERROR, and the connection is torn down with a plain TCP FIN (not a TLS alert) roughly 7-8ms after our side ACKs the server's Finished message. - TCP_Client.eErrorID (inherited from LCon) remains NO_ERROR throughout - the failure is only visible via Upgrade()'s return value. - Returning 0 (ERR_OK/ERR_CERT_OK - confirmed via the CmpErrors2 Interfaces documentation that these are literally the same value) makes no difference. - Echoing eCurState back unchanged (on the theory that this callback might work like mbedTLS's native verify callback, where the incoming state is a flags value to be cleared/modified and returned, rather than paired with a separate fixed "accept" sentinel) also makes no difference. - Identical result across udiVerificationMode := 0, 1, and 2. - Importing the peer's certificate into the runtime's trusted certificate store via cert-import trusted makes no difference either. - With itfCertVerifer left at its default (no custom verifier) and udiVerificationMode := 2, the underlying engine sends its own fatal TLS alert (handshake_failure) immediately after receiving the peer's Certificate message - suggesting built-in validation may reject at the record layer independent of whether a custom verifier is even present. Questions: 1. Is there an additional step required for a custom ICertificateVerifier to actually override an ERR_CERT_HAS_EXPIRED (or more generally, any ERR_CERT_*) rejection, or is certificate validation enforced unconditionally for a CLIENT_SIDE TLSContext regardless of what the verifier returns? 2. Is 0/ERR_OK genuinely the correct "accept" return value for VerifyCertificate, or does it expect something else (a specific bit pattern, a different constant, a value that must be computed from hCert itself)? 3. Is there a supported way to connect to a peer presenting a certificate that is both self-signed and expired, short of the peer issuing a new certificate? Happy to share the full packet captures or additional test combinations if useful. Also worth noting for anyone finding this thread later: a maintained Node-RED library for this same device (node-red-contrib-velux-klf200, forked to handle this exact expired-certificate situation) solves it by disabling built-in TLS validation entirely (rejectUnauthorized: false) and doing fingerprint-based pinning by hand after the handshake completes, rather than relying on a validation callback - which may be the more realistic approach here too if ICertificateVerifier genuinely can't override this class of rejection. Thanks in advance /Jørgen Disclosure: most of the CODESYS code and this investigation was developed with the help of Claude (Anthropic's AI assistant) - the state machine design, SLIP/checksum implementation, and debugging methodology (including the packet capture analysis) were worked through in an extended back-and-forth with it. Posting here because we've run out of self-serviceable options and this now looks like it needs input from someone with visibility into NBS's actual implementation.
Last updated: 2026-07-26

Post by adamrobotic on llcallback() iec exception caught cmpid=0x00000002, eventid=0x00010008 ^{CODESYS Forge talk (Post)}
Hi All, Recently I have been experiencing a issue in CodeSys SP16 Patch 3, with a exception which comes up after I have made several online changes. callcallback() iec exception caught cmpid=0x00000002, eventid=0x00010008, after I experience this fault then I receive a error message for any subsequent online change "online change failed, no task gap within 10000ms". To recover either the controller needs a orgin reset, which will allow online edits thereafter until falling back into the loop. I am using a TURCK TX707 product which is controlling robot trajectory, We have hard coded the coordinate data rather than using persistence variables so hence the need to do online changes consistently. I have read on the forum other people have experienced similar issue with the online task gap, but I have no task which have same priority and also monitored the CPU usage and have not seen it go above 13%. Anyones help would be much appreciated, thankyou.
Last updated: 2023-08-18

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 ofey on Codesys Soft PLC OPC UA server ^{CODESYS Forge talk (Post)}
Hi! I'm sorry if this has been asked before. I have tried looking up previous topics regaring this, but even though I'm following tutorials and other posts I cant seem to get this to work consistently. I actually got the connection established on a test project after some trial and error. I only got it to work with the "Anonymous login". But after i deleted the test project and tried to get the same thing to work on another project I cant get it to work anymore. What I'm trying to do: Set up and OPC UA Server using CODESYS with the free soft PLC. I then try to connect to the OPC UA Server with the program "UaExpert". What happens: I get the error Error "'BadUserAccessDenied' was returned during ActivateSession". What I have done in CODESYS: - Added the object "Symbol configuration" and checked some test variables - Checked "Support OPC UA features - In "Communication settings -> device -> Change runtime security policy" I have checked "Allow anonymous login" What I have done in UAExpert: - Found the OPC UA server under "local". (It is showing two servers though, I do not know why. It showed the same when it worked yesterday). Se attachment - Checked "Anonymous" under "Authentication settings in the OPC UA server. I'm new to CODESYS, so it could be something elementary wrong in my settings. Maybe something in the user settings in CODESYS regarding user rights or something?
Last updated: 2023-09-14

Post by manuknecht on Persistence Manager does not save alphabetically first value ^{CODESYS Forge talk (Post)}
I have several libraries which contain values that should be saved on a PLC. As apparently no Persistent Variable List is available within Libraries, I use the Persistence Manager to create a Persistence Channel in the Project which imports the library. I then specify the persistence channel in the library using the {attribute 'ac_persist':='PersistenceChannel_CT'} specifier. This generally works very well and gives me exactly the properties I require. However, it came to my attention that the (alphabetially) first value from the library is not saved in the created ASCII file. When checking the content of the Persistence Channel, it shows all the variables as defined in the library. But the created file does not contain the first value and it is not restored after restart or reset. (see attached picture) I disabled Periodic Saving and set xSaveOnChange to TRUE and so the file usually updates immediately after changing one of the values. When changing the first value, it does not update which is consistent with this value not being saved. I also created a sample project and library from scratch which shows the same issue both using a Raspberry Pi and using a Linux machine. Does someone know what the reason for this could be or did someone make similar experiences? Looking forward to hearing your suggestions. Thanks in advance and best wishes Manuel
Last updated: 2023-10-17

Post by vassilis91 on EtherCat-Rexroth Drive lost connection or no? ^{CODESYS Forge talk (Post)}
Hi all, i am encounter a mystery problem with a build with rexroth drives at my work. At my company we are make a machine with two Rexroth Indradrives . The two drives are goes by ethercat protocol . To be more specific i am going from my plc to the Beckoff El1100 coupler and after to the first drive and from the first drive to the second. The second drive works with no problem but the first(motor) sometimes without any pattern start to make a mysterious noise like stop and suddenly goes on again. If i couldn't hear the noise from the motor i couldn't Imagine that this happen. After a lot of research i see that sometime i have some strange zeros from the drive to the plc? Really i am in a deadlock and I don't know how to continue. From the other side the values on the other drive(second)are stable . The problem maybe: https://youtube.com/shorts/g7PCFLUaDUI?si=eiq0F2IzhQZax2e2
Last updated: 2023-10-25

Post by abinvest579 on TCP Client ^{CODESYS Forge talk (Post)}
Hi All, I am using codesys based plc to read and control magna power DC supply over LXI protocol using SCPI command. To connect device required socket programming for that i am using Net base service library function block TCP_Client to establish connection over TCP/IP , TCP_Write to write SCPI commands and TCP_Read to read data from Magna power DC supply. I have attached screenshot for logic developed. I am able to connect and write commands to device but i not receiving any information from device. For writing Commands i also tried various end of line character like \n,<nl>, A, D, 10, 13, 0x0A, 0x0D but not received any status from device. For testing purpose i am using simple command '*IDN?' to read data. Also if tried to check on hercules software what data actually plc read, first it read correct data after that is read wrong data as see in screen shot. 'Hello World' was correct read and after that Codesys in replaced with 'Codesysorld' that is not correct way. Same issue also appeared for send data. Any one have face same issue how i can read data directly from device correctly and send data please suggest solution on this.</nl>
Last updated: 2024-07-01

Post by wbj0t on What the right way to update TCP/COM slave device holding registers ^{CODESYS Forge talk (Post)}
Hi all :) I have an plc. This plc has option to be as slave device. There are TCP -> Serial Slave Device and COM -> Serial Slave Device. There are 4096 ModBus holding registers with mark "internal modify" for the both devices above. So, COM Slave has 4096 registers and TCP Slave has 4096 registers. And, finally, I have an ARRAY[0..4095] OF WORD. This array glued with COM Slave and TCP slave. Yes, I need plc's opportunity to be communication both TCP and COM ways for the same registers. For example, the next task structure: * TASK_0: 1. pou_READ_Registers 2. pou_0 3. pou_1 4. ... 5. pou_N 6. pou_WRITE_Registers At the first pou I read registers for the other pous, after job we have sort of state of the plc. At the last pou (6) we write modified registers. It is a good scenario: some one wrote registers for the job, after job we save these (modified) registers. But, what if registers wrote between 1 and 6 pou by operator, for example, at the 3 pou -> the last pou 'pou_WRITE' will rewrite this request from operator. What the right way to work with this logic? Thanks you.
Last updated: 2024-07-01

Post by egau on Hard shutdown: no code on device after power on ^{CODESYS Forge talk (Post)}
Hi, We have a machine running Codesys on a Windows IPC (CODESYS Control Win v3 - x64). When we hard shutdown the machine, the code on the PLC sometimes becomes "corrupted" after a power on (When trying to login to the PLC, we get the message "The application 'Application' does not exist on device."). I've noticed these errors in the logs, but I'm not sure what to make of them. We are not using any RETAIN variables in our code, although I'm not sure about referenced librairies. (we are using the persistence manager). I'm pretty sure that not doing a graceful shutdown is the root cause of this. This being said, what is the proper way of doing a graceful shutdown? Is putting the Codesys application in "stop" sufficient? I know how to implement this, so if it works then it would be a quick fix. However, I think we need to add a UPS, which would detect power loss and inform the PLC that it needs to initiate its shutdown, and then the PLC would shutdown gracefully. Any help with this will be greatly appreciated :)
Last updated: 2024-10-03

Post by mubeta on Profibus DP master with EL6731 and automatic restart of slaves ^{CODESYS Forge talk (Post)}
WHEREAS, I have already searched various posts and forums, where mostly there are few references and mostly geared toward integration in TwinCAT. I am looking for how to properly configure the EL6731 board as a DP master, (where I have its 3S license), with CoDeSys 3.5.19.x. I have three types of slaves, all integrated with their GSD descriptors. In the tab for the various slaves, I don't see options related to node restart on 'station return'. On the card manual, I read that for each slave I should be able to configure parameter 8000:2C: “8000:2C Restart behavior after DP fault Reserve, must be 0 BIT1 RW 0x00 (0dec)” However, in the project I see no way to configure this parameter, in any of the boards; and the arrays do not always have such an extensive size; most of the time they are only two or three words in size. The problem is that, after the hot reset of CoDeSys, the master restarts by starting all slave nodes, but if one or more get lost and go offline, there is then no automatic restart upon their return. I would need to figure out any solution, even via software, how to figure out that this one is back available and restart it.
Last updated: 2025-02-02

Post by alexgooi on Licensing info not available. ^{CODESYS Forge talk (Post)}
Sorry for the question, but I'm not completely getting the idea here, could you be more specific, maybe give an example? I'm now in a state where I don't have a softcontainer on my license server anymore (even after reinstalling from the Codesys-IDE). I tried reaching the webserver of Codemeter but when I do that I get redirected to http://"IP":22352 This is not reachable, afterwards I installed lynx on my Debian machine (command line only). From here I could reach the webserver and toggle the network server setting, but unfortunately this did not help. I also tried to changed the remote read setting to 1 (in the Server.ini file). But after a Codemeter reboot this is overwritten to 0. I have the feeling that it should be much easier to get a license to work, am I missing some checkbox somewhere? Is there a tutorial (or manual) that explains the licensing sequence step by step, because I'm pretty stuck.
Last updated: 2025-10-01

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 brell on Automatic xExecute NBS.TCP_write ^{CODESYS Forge talk (Post)}
I've recently started experimenting with CODESYS for a project and am fairly new to it. I'm currently working with Function Block Diagrams (FBD) to set up TCP communication between a server and a client, where the client is implemented as a Python script. Once the communication is established, my connection status changes to True, which is the expected behavior. My challenge arises with the TCP write module, which requires the xEnable_write flag to toggle between True and False. If xEnable_write remains True, the module only performs a single write operation. To address this, I introduced a falling edge trigger (F_TRIG), expecting it to help in toggling xEnable_write and it does, However, I've encountered an issue where in the beginning after connxion established I need to manually set xEnable_write to True for the system to work as intended. I'm looking for a way to automate this process so that xEnable_write becomes True automatically upon establishing a connection . Initially, I tried setting xEnable_write to True from the start, but this approach didn't work well since it left the flag permanently True, preventing further toggling. I also experimented with using a TON timer, but I faced similar issues. I am seeking a solution that automatically toggles xEnable_write between True and False after a connection is established, ensuring continuous write operations without manual intervention. Any advice or guidance on how to achieve this would be greatly appreciated."
Last updated: 2024-03-05

Post by rjwkerkhof on IIot Libraries SL --> Web Socket Client SL Pong issue ^{CODESYS Forge talk (Post)}
Dear all, I am developing a Web Socket Client in Codesys 3.5 using the Web Socket Client SL library to retrieve data from a third party. Connecting and reading works fine however after 40 seconds the connection gets interrupted by the server due to keepalive ping timeout. After discussion with third party it seems that the Web Socket Client SL library replys to the Ping request of the Web Socket server BUT does not add the "Application data" = 4 bytes in the body of the Pingframe to the Pongframe. Therefor the server does not recognize the Pongframe send by the Web Socket Client SL library and automatically disconnects. Is this a known issue with the libary or am I doing something wrong? Is there a workaround to add the 4 bytes manually to the Pongframe before replying it to the server? Thanks in advance, Roy
Last updated: 2024-04-09

Post by culius on JSON ^{CODESYS Forge talk (Post)}
Hey guys, I am trying to write a JSON. First time after login in PLC after download everthing works. But when I want to change values during runtime and try to recreate the JSON nothing happens. When forcing the xStart as an impulse i want to recreate it and see 2 as Key3 instead of 1 from the first run. Any Idea how to make this work? PROGRAM test VAR factory : JSON.JSONDataFactory; eDataFactoryError : JSON.FBF.ERROR; pJsonData : POINTER TO JSON.JSONData := factory.Create(eError => eDataFactoryError); fb_JBuilder : JSON.JSONBuilder; wsValue : WSTRING; diRootIndex, diObject1Index : DINT; iValue : INT; jsonArrayWriter : JSON.JSONByteArrayWriter; wsJsonData : WSTRING(1000); xFirst : BOOL := TRUE; END_VAR IF xFirst THEN fb_JBuilder(pJsonData := pJsonData, diRootObj => diRootIndex); wsValue := "Value1"; fb_JBuilder.SetKeyWithValue("Key1", wsValue, diParentIndex := diRootIndex); diObject1Index := fb_JBuilder.SetKeyWithObject("Key2", diParentIndex := diRootIndex); iValue := iValue + 1 ; // -----------!!! secound run should increment key3!!!!------------ fb_JBuilder.SetKeyWithValue("Key3", iValue, diParentIndex := diObject1Index); xFirst := FALSE; END_IF jsonArrayWriter(xExecute := TRUE, pwData := ADR(wsJsonData), udiSize := SIZEOF(wsJsonData), jsonData := pJsonData^, xAsyncMode := FALSE); Kind Regards
Last updated: 2024-04-30

Post by valenting on License problem with Raspberry Pi ^{CODESYS Forge talk (Post)}
Hello, I have a raspberry pi with a license installed, but Codesys stops after 2 hours, and when I start it manually I have the following message: pszInfo=!!!! no runtime license - running in demo mode(~2 hours) I tried using License Manager, and got the following message: Licensing info not available. There is no dongle attached to the device. I have this message frequently, and usually removing the content of /var/opt/codesys/.cmact_license makes it work. After doing it and restarting Codesys, I have an empty Softcontainer without my License. I tried using "Install license" using the .WibuCmRau file for the corresponding license and got the following message: Licensing info not available. The device does not support this service. I also tried using Additional Functions > Restore Licenses with the Ticket ID and got the following message: This device does not support automatic license backup. How can I reinstall the license to this Raspberry Pi?
Last updated: 2025-11-28

Post by mrkm-dic on UC20-M4000 Redundancy – Application is not automatically synchronized and redundancy breaks after online change ^{CODESYS Forge talk (Post)}
Hello, I am currently testing redundancy using two UC20-M4000 controllers with CODESYS Control SL. The basic redundancy functionality (Active/Passive switching and failover) works, but I am experiencing problems when updating the application. Environment Controller: Weidmüller UC20-M4000 OS: u-OS Runtime: CODESYS Control SL 4.12.1.0-1 Redundancy link: dedicated Ethernet connection between the two controllers Time synchronization: NTP configured, time difference between controllers is about 1–2 seconds Current behavior Application synchronization When I download a modified application to PLC1 (Active controller), the application is not automatically copied to PLC2 (Passive controller). However, when I perform a path swap, the application download to PLC2 starts automatically. My expectation was that the Passive controller would automatically receive the updated application after downloading to the Active controller. Online change When performing an online change, redundancy is lost and the controllers switch to Standalone mode. Typical log messages include: RedundancySynchronize called Redundancy failover itself works correctly. The application boot project exists on both controllers (Application.app and Application.crc). Network interfaces are up and correctly configured. Question Is this behavior expected when updating the application in a redundant UC20-M4000 setup? Should the Passive PLC automatically receive the updated application, or is manual synchronization required? Any advice or recommended configuration for stable redundancy during online change and application download would be greatly appreciated. Thank you.
Last updated: 2026-03-16

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

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