Post by micik on Using Codesys example problems
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Hello to all, I'm totally new to Codesys, but I do have some PLC programming experience, mosty with Siemens TIA and STEP7. I have just installed Codesys 3.5. sp19 and I have downloaded example with Ethernet Rockwell 1734AENT. The example can be found here: https://forge.codesys.com/prj/codesys-example/rockwell-1734-c/home/Home/ After opening, I had to manually update devices (Device, Ethernet, IP Scanner, EthernetIP adapter). However, when trying to build the project, I get the following errors: [WARNING] CODESYS_EtherNetIP_Rockwell1734AENT: Library Manager [Device: PLC Logic: Application]: C0100: Library System_VisuElemXYChart has not been added to the Library Manager, or no valid license could be found [WARNING] CODESYS_EtherNetIP_Rockwell1734AENT: Library Manager [Device: PLC Logic: Application]: C0100: Library system_visuinputs has not been added to the Library Manager, or no valid license could be found [ERROR] iodrvethernetip, 4.4.1.0 (3s - smart software solutions gmbh): ServiceCycle [IoDrvEtherNetIP]: C0040: Function 'ProcessUpdateConfigurationQueue' requires exactly '1' inputs [ERROR] iodrvethernetip, 4.4.1.0 (3s - smart software solutions gmbh): IoDrvStartBusCycle [IoDrvEtherNetIP]: C0040: Function 'GenerateRandomUINT' requires exactly '2' inputs [ERROR] iodrvethernetip, 4.4.1.0 (3s - smart software solutions gmbh): Cyclic [GenericServiceUnConnected]: C0040: Function 'GenerateRandomUINT' requires exactly '2' inputs [ERROR] cip object, 4.4.1.0 (3s - smart software solutions gmbh): ForwardOpenService [ConnectionManager]: C0040: Function 'GetAssemblies' requires exactly '3' inputs [ERROR] iodrvethernetipadapter, 4.4.0.0 (3s - smart software solutions gmbh): ServiceCycle [IoDrvEtherNetIPAdapter]: C0040: Function 'GenerateRandomUINT' requires exactly '2' inputs [ERROR] iodrvethernetip, 4.4.1.0 (3s - smart software solutions gmbh): SetupStructuredIOMapping [RemoteAdapter]: C0040: Function 'MallocData' requires exactly '1' inputs [ERROR] iodrvethernetip, 4.4.1.0 (3s - smart software solutions gmbh): SetupStructuredIOMapping [RemoteAdapter]: C0040: Function 'MallocData' requires exactly '1' inputs Compile complete -- 7 errors, 13 warnings Build complete -- 7 errors, 13 warnings : no download possible! What could be the reason for this errors and how to rectify them? Thank you!
Last updated: 2024-02-01
Post by thn-power on Updating OPC UA Core Nodeset on PLS
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Hi After much trail and error I think I found the root cause to my OPC UA problem. The problem is that I cannot manage to build and download a program with a a custom OPC UA Information model. We use a Weidmueller WL2000 PLS, but the problem also exsist on the Win V3 PLC. Our custom information model is based on the latest versions of the OPC UA Core Nodeset v 1.05.03 (2023-09-20) and UA/DI nodeset 1.04.0 (2022-11-03) Those nodesets are installed in the Codesys Information Model Repository (3.5.19.6) However, when trying to build I get the following error. [ERROR] Untitled1: Communication Manager [Device: PLC Logic: Application]: The information model http://opcfoundation.org/UA/ is required by http://bos.org/ with a minimal publication date from 15.12.2023 but the device has only a model from 15.09.2021 installed. Probably the information model from 15.09.2021 is missing in the information model repository. [ERROR] Untitled1: Communication Manager [Device: PLC Logic: Application]: The information model http://opcfoundation.org/UA/DI/ is required by http://bos.org/ with a minimal publication date from 03.11.2022 but the device has only a model from 09.03.2021 installed. Probably the information model from 09.03.2021 is missing in the information model repository. Build complete -- 2 errors, 1 warnings : No download possible I think the problem is that the UA Core nodeset is implemented in the PLC firmware (at least that in Siemens S7), and that only includes the "old" nodeset from 2021-09-21 etc. So the question is, how (or if?) can I transfer the new nodeset to the PLS? I have created separate Information models under Communication manager with the newer code nodesets (UA and DI). But it seems that the compiler does not recognize them being excising, neither in the Codesys IDE or on the PLC. Would have guessed that this is a common issue, sine many manufacturers use the latest versions of the OPC UA standard, and that it would be a solution to the problem.
Last updated: 2024-09-20
Post by danwoodlock on RPI Zero w - Edge gateway cant install
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Hello all, First post. I recently acquired an RPI zero W from amazon, and have been using it with Codesys v3.5 SP19 patch 2. I first got it working yesterday, and after installing the runtime on the Pi, I was prompted to install the edge gateway. Installation of the edge gateway failed because of unsupported architecture, undeterred I was able to connect to the pi and program as I wanted. The issue I've noticed is that if I do not load anything to the pi overnight, I can then no longer connect to the pi and download, although I can still ping it from my pc. I found that if I power cycle the PI, I am then able to connect again, and it works as normal. I did some googling and found instances where people recommended downloading the newest edge gateway, which brings me here. Wondering if there are any suggestions, or if this is a known issue. I actually tried installing all 3 versions of edge gateway for science, but all fail with the same message. Thanks -Dan
Last updated: 2023-09-13
Post by marek71 on Ambiguous use of name - CO136
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My PLC is WAGO PFC200 Firmware Revision 26. target After updating WAGO_Devices_and_Libraries with newer Firmware 27, CODESYS wants to update all libraries to new versions. I will only add that I did not update the Firmware in the PLC. After compiling the program, I received the following errors: ------ Build started: Application: Device.Application ------- Typify code... [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): FbSerialInterface_internal: C0136: Ambiguous use of name 'RTS_IEC_HANDLE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): FbSerialInterface_internal: C0136: Ambiguous use of name 'RTS_IEC_RESULT' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): Initialize [FbSerialInterface_internal]: C0032: Cannot convert type 'Unknown type: 'RTS_INVALID_HANDLE'' to type 'POINTER TO BYTE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): Initialize [FbSerialInterface_internal]: C0136: Ambiguous use of name 'RTS_INVALID_HANDLE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): Initialize [FbSerialInterface_internal]: C0046: Identifier 'RTS_INVALID_HANDLE' not defined [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): comextra_is_tx_empty: C0136: Ambiguous use of name 'RTS_IEC_HANDLE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): comextra_get_line_state: C0136: Ambiguous use of name 'RTS_IEC_HANDLE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): comextra_is_line_available: C0136: Ambiguous use of name 'RTS_IEC_HANDLE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): COMSW_SET_MODE: C0136: Ambiguous use of name 'RTS_IEC_HANDLE' [ERROR] wagosyscom_internal_pfc, 1.0.2.5 (wago): comextra_set_line_state: C0136: Ambiguous use of name 'RTS_IEC_HANDLE' Compile complete -- 10 errors, 0 warnings Build complete -- 10 errors, 0 warnings : No download possible The problem was caused by the WagoSysPlainMem(WAGO) library in the original version 1.5.3.0 after updating to 1.5.3.1. After returning to version 1.5.3.0, the problems disappeared. Probably the version number of this library is responsible for supporting the appropriate Firmware Revision. Can anyone confirm or deny my suspicions?
Last updated: 2024-07-06
Post by sbhaskarla on WebVisu File Transfer Error
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I’m encountering an issue when downloading CSV files via the WebVisu button input config -> file-transfer option: • Custom directory: /plcdata/csv_logs/filename.csv o Error: Error 4 – Error during file transfer • Sandbox directory: /var/opt/codesys/PlcLogic/plcdata/csv_logs/filename.csv o Result: Download succeeds without error. Actions taken so far: 1. Added /plcdata/csv_logs to codesyscontrol.cfg (see attached). 2. Enabled file-transfer services in codesyscontrol_user.cfg (see attached). 3. Confirmed that the PLC writes CSV files correctly to /plcdata/csv_logs/. Despite these settings, WebVisu still returns Error when accessing the custom path 1. Using the placeholder file path '$$CSVLOGS$$/filename.csv' and it returns Error 6. 2. Using the literal path /plcdata/csv_logs/filename.csv and it returns Error 4 Could someone please help me determine what additional configuration or troubleshooting steps are required to serve files from /plcdata/csv_logs/? Please find screenshots attached for better understanding and I have also attached the config files
Last updated: 2025-06-13
Post by brubingh on Download Missing Libraries not working
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We are working on a project and the customer required 3.5.16 BF4. After working on the project for a few weeks I opened it the next morning and it could not access libraries. IecVarAccess could not be accessed. I checked if windows updated - it did not. So no explanation for why it lost access other than that I shut down the computer for the night. Note that I am using a demo license. I still haven't figured out any reason to purchase a license. So I spent the next hour reinstalling CodeSys. Note that I did NOT uninstall first. After install I waited another 5 minutes for it to open the first time. I clicked File->Open to open the project. Previously I had selected File->Recent Projects - not sure if that makes and difference. But after this process it did open the project and compile it just fine. This is miserable. If this had happened when I went on site to a customer I would have lost hours of work doing the reinstall. Is there a different and quicker fix?
Last updated: 2024-06-13
Post by shamcke on Array with generic constant as persistent variable
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Hello, I have written a function block that uses a generic constant for the upper bound of an array. I wanted to have this array in the persistent memory area, thus I constructed my FB as follows: FUNCTION_BLOCK FbWithGenericArrayLength VAR_GENERIC CONSTANT uiArrayLength : UINT := 10; END_VAR VAR PERSISTENT arr : ARRAY[1..uiArrayLength] OF INT; END_VAR In my PLC_PRG I declare an instance of said FB PROGRAM PLC_PRG VAR myFb : FbWithGenericArrayLength<10>; END_VAR This compiles just fine. When I let CODESYS fill my persistent list, it adds duplicate entries {attribute 'qualified_only'} VAR_GLOBAL PERSISTENT RETAIN // Generated instance path of persistent variable PLC_PRG.myFb.arr: ARRAY [1..uiArrayLength] OF INT; // Generated instance path of persistent variable PLC_PRG.myFb.arr: ARRAY [1..uiArrayLength] OF INT; END_VAR so I manually delete the duplicate. When i now compile, I get errors ------ Build started: Application: Device.Sim.Device.Application ------- Typify code... [ERROR] Sandbox_FW31: PersistentVars [Device: PLC Logic: Application](Line 4): C0161: Border 'uiArrayLength' of array is no constant value [ERROR] Sandbox_FW31: PersistentVars [Device: PLC Logic: Application](Line 4): Type of mapped variable is not equal to original type Compile complete -- 2 errors, 0 warnings Build complete -- 2 errors, 0 warnings : No download possible Is is simply not possible to use a generic constant for the persistent array? Thanks in advance. Edit: It seems I can manually replace the uiArrayLength in the persisten list by the value 10 I used as the generic constant for this particular instance.
Last updated: 2026-05-29
Post by eschwellinger on Beispieldateien finden / Inhalt der Packages
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ja danke hilft definitv & sorry- das wird verbessert, kĂĽnftig werden die Packages & Beispiele nach "c:\Program Files\CODESYS <version>\CODESYS\CODESYS Control for Raspberry PI\<version>\Examples\" installiert werden.</version></version> Beispiel fĂĽr die PI Beispiele: "c:\Program Files\CODESYS 3.5.19.30\CODESYS\CODESYS Control for Raspberry PI\4.10.0.0\Examples\" dass wird fĂĽr alle Aktualisierungen/Updates der Packages so ausgerollt.
Last updated: 2023-11-17
Post by davecfc on Codesys installation package fails because not signed
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Also had this problem when working on legacy project. My packege was CODESYS Code Generator ARM 4.0.3.0.package. To manage this I used PackageManagerCLI.exe. This tool does not validate certificates appearently. My command: "C:\Program Files\CODESYS 3.5.17.30\CODESYS\Common\PackageManagerCLI.exe" --profile="CODESYS V3.5 SP17 Patch 3" --install=""C:\Users\sample_user\AppData\Local\Temp\APInstaller\5wx1k02a.r2t\CODESYS Code Generator ARM 4.0.3.0.package""
Last updated: 2024-04-18
Post by thierry-b on Blocking UDP ports 1740–1743 and 22350 to disable CODESYS network scan (startup + device discovery)
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Hello, I am currently investigating the network behavior of CODESYS 3.5 (IDE + Gateway) in environments where the engineering workstation is connected to a very large /16 network. In such networks, the automatic device scan performed at IDE startup (and the manual “Scan Network” device discovery) can cause significant delays or freezes, due to the broadcast‑based discovery mechanism. After analyzing the traffic with Wireshark, I identified that the IDE uses the following UDP ports: 1740 – broadcast discovery 1741 – handshake / responses 1742 – fallback discovery 1743 – fallback handshake 22350 – additional runtime / gateway communication (WAGO, debug, extended discovery) To prevent the IDE from scanning the large /16 network, I tested blocking these ports in both directions (IN/OUT) on the network interface connected to the /16 segment (while keeping them open on the OT /24 network interface). Result: When UDP 1740, 1741, 1742 and 1743 are blocked on the IT interface, the IDE no longer sends any discovery traffic on that interface. The IDE still works normally on the OT interface (device discovery, online mode, download, etc.). Blocking port 22350 does not seem required to stop the scan, but I included it for completeness. My question: => Can you confirm that blocking UDP ports 1740, 1741, 1742, 1743 (and optionally 22350) on a specific network interface is a valid and supported way to completely disable the CODESYS IDE network scan on that interface (both at startup and during manual device discovery)? I am not trying to block communication with controllers on the OT network — only to prevent the IDE from scanning the large /16 IT network. Any confirmation or additional technical details about the discovery mechanism would be greatly appreciated. Thank you.
Last updated: 2026-03-31
Post by bschraud on runtime received SIGABRT
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Hallo, seit der Umstellung meines Projektes auf die aktuelle Codesys Version mit aktuellen Bibliotheken und Aktualisierung der Runtimer Version bekomme ich im Zeitraum 15min bis 1h nach Neustart des Target Systems folgende Fehlermeldung: runtime received SIGABRT - system may be in an inconsistent state Der Fehler kommt auch nach dem Start des Systems ohne eine Benutzeraktion zuverlässig, aber in unterschiedlichen Zeiträumern. Hier sind die Logs und Daten, die ich dazu ermitteln konnte: $ tail -f /var/opt/codesys/codesyscontrol.log 2025-04-03T06:54:37.659Z, 0x0000100c, 1, 0, 0, Visu_PRG: Creating Client for Extern-ID: 594337835 2025-04-03T06:54:37.660Z, 0x0000100c, 1, 0, 0, Visu_PRG: Creating Client successful for Extern-ID: 594337835 Returned IEC-ID: 0 2025-04-03T07:01:38.135Z, 0x00000103, 65544, 1, 0, runtime received SIGABRT - system may be in an inconsistent state * We recommend a reboot of the controller now! 2025-04-03T07:01:38.135Z, 0x00000111, 8, 260, 3, #### Exception: HANDLED EXCPT* <excpt>NonContinuable</excpt> in CH_COMM_CYCLE 2025-04-03T07:02:18.181Z, 0x00000103, 65544, 1, 0, runtime received SIGABRT - system may be in an inconsistent state * We recommend a reboot of the controller now! 2025-04-03T07:02:18.181Z, 0x00000111, 8, 260, 3, #### Exception: HANDLED EXCPT* <excpt>NonContinuable</excpt> in CH_COMM_CYCLE $ vmstat 1 procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st 1 0 0 271120 33976 342284 0 0 135 2 2387 4751 10 7 82 1 0 1 0 0 271024 33976 342380 0 0 0 0 10163 20427 10 9 81 0 0 1 0 0 271056 33976 342380 0 0 0 0 8455 16869 9 5 86 0 0 0 0 0 271040 33976 342380 0 0 0 0 8674 17484 9 4 87 0 0 0 0 0 271072 33976 342380 0 0 0 0 10070 20350 7 7 87 0 0 1 0 0 271040 33976 342380 0 0 0 0 10354 20802 10 6 84 0 0 0 0 0 271072 33976 342380 0 0 0 0 8401 16923 8 6 86 0 0 $ vcgencmd measure_temp temp=56.9'C $ uname -a Linux PAC4 5.10.103-v7+ #1529 SMP Tue Mar 8 12:21:37 GMT 2022 armv7l GNU/Linux CODESYS V3.5 SP21 Runtime: Codesys control for Raspberry Pi MC SL V 4.13.0.0 Hinweise auf ein instabiles OS oder instabile Netzwerkverbindungen konnte ich keine finden. In dmesg und im syslog gibt es keine Auffälligkeiten. Die anderen Posts zu diesem Thema wurden nicht beantwortet. Hat jemand einen Tip, wie man an das Problem herangehen kann? Vielen Dank
Last updated: 2025-04-03
Post by taqamert on Codesys 2.3 & Peak PCAN
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I will use Codesys to program a PLC. I will connect the PLC to the computer via the CAN interface using PEAK CAN, but Codesys does not recognize the CAN adapter. I have added the following libraries. What should I do? What steps should I follow?
Last updated: 2024-07-03
Post by joelwright24 on codesys sp20 opcua not working
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I also had this problem connected CODESYS to UAExpert for the first time. In the device, I need to allow anonyomous log in. Follow steps 14 - 17 of the following tutorial: https://docs.factoryio.com/tutorials/codesys/setting-up/codesys-opc-ua-sp17/#creating-the-project
Last updated: 2024-09-11
Post by timvh on CoDeSys 3.5 SP20 "No Offline Help installed"
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Open the CODESYS Installer (from the menu Tools). Go to Browse. Search for: help ... Select the CODESYS Offline Help which you would like to install. (probably you have to close CODESYS to install it and reopen it after installation).
Last updated: 2024-10-01
Post by timvh on Codesys Control for PLCnext (PLC - AXL F 2152)
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Do not filter on Phoenix devices. First add an Ethernet device (from CODESYS). Then add a Profinet Controller (from CODESYS). Then add your Phoenix devices to this CODESYS Profinet Controller.
Last updated: 2025-09-09
Post by davidbo on Does CODESYS use its own native driver for I2c?
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CODESYS Control for Raspberry Pi MC Does CODESYS use its own native driver for I2c? I have a python script communicating with a device simultaneously with a CODESYS doing the same. The bus is not saturated. But I get many read errors
Last updated: 2024-02-13
Post by simonep on new version of CODESYS have problem to load GSDML files
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I have update codesys today but now i can't install my GSDML files, until Friday I was always able to load without any problem, now it gives me this error. Codesys version V3.5 SP19 Patch 1 + (64 bit)
Last updated: 2024-05-20
Post by ranadheer on conformation about the CODESYS Extends SL and CODESYS SDK
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hello everyone would anyone here respond, Is CODESYS Extends SL and CODESYS SDK are same. If both are not same could you please give related data about this. Best Regards Ranadheer
Last updated: 2025-11-10
Post by patrik on Wish: CODESYSControl.cfg - again
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Really good post. I hope that it gets seen by CoDeSys staff. I often find the documentation lacking when it comes to using CoDeSys in more complex ways. If using standard "basic PLC functionality", then it's fine and functions are documented in a sufficient way. Once you go outside of that bubble then I find the documentation not enough. CODESYSControl.cfg is a good example of this. And why isn't more of this integrated in the IDE. like changing port of the webserver. Why is it hidden in this file and not accessible through the IDE. It feels like a layer of complexity purposely left in so you don't change it if you don't know what you are doing. Like the argument is if you have the know-how to find the file you have the know-how to edit it. I find the documentation lacking when it comes to more complex libraries too. Like the element collections library. there is parameters I still don't quite know what they do. I can't find any documentation about them. There is an example project to download from CoDeSys so you can see how you are supposed to set your factories up. I leave some parameters like it is in the example. Should I? I don't know. Does it work. Yes. But I could perhaps create memory leaks if I get something wrong and I don't see that until way later. In the create method of your element factory you have a function called __vfinit and you just have to accept that it works. Why can't I get insight in what it does through documentation? Don't CoDeSys want us to know how these work so we can't use them to accidentally break something? I find the error logging lacking too. I've had the CoDeSys service crash but it doesn't say why. I've seen windows noticing the crash but no error code was sent or error message. Also in my current issue where the application fails to start after power outage. I can see in the log that it fails to load retain in the application as one log entry and application failing to start as another. But why? Why does loading the retain fail? give me more information! Is it just a skill issue with me? I don't know. If it is then I'd still want CoDeSys to step up their game when it comes to documentation. I'm sorry if a lot of frustration comes though in this post. I really like the product and what I can do with it compared to other PLC brands.
Last updated: 2024-11-21
Post by sahin6033 on DSE M840-001-02: DSEServiceTool transfers CodesysApp.pkg successfully, but device shows “No application loaded
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Hi, I am trying to load a test application into a DSE M840-001-02 display, but after reboot the device still shows: “No application loaded” I would like to understand whether the problem is in my project, the package creation process, or firmware/runtime compatibility. Hardware Device: DSE M840-001-02 Firmware used: M840 MKII Firmware File v4.1.2 Software CODESYS V3.5 SP12 (32-bit) DSE CODESYS Package v1.5.44 DSEServiceTool What I did Created a new empty Standard Project Selected target/template: M840-02 V4.1 Used a minimal ST program only: PROGRAM PLC_PRG VAR xAlive : BOOL := TRUE; END_VAR Confirmed: project builds PLC_PRG is assigned to MainTask created Boot Application Generated CodesysApp.pkg Put the M840 into bootloader mode Sent the package using DSEServiceTool DSEServiceTool result Transfer completes successfully and I get: connection accepted 100% download package ACK <status>OK</status> ** Example log:** Searching for controllers.... sendPackageToController: waiting for incoming data connection... sendPackageToController: connection accepted... <status>Downloading</status> <percent>20</percent> <percent>40</percent> <percent>90</percent> <percent>100</percent> sendPackageToController: sent 112cb8 bytes OK Package ...\CodesysApp.pkg transferred to controller c0a80101 OK sendPackageToController: package ACK <status>OK</status> Actual result After reboot, the display still shows: “No application loaded” Additional issue I also saw earlier At one stage I also had these fatal errors in CODESYS: [FATAL ERROR] Unresolved reference: 'IOMGRLOCKENTER' [FATAL ERROR] Unresolved reference: 'IOMGRLOCKLEAVE' I checked library versions and adjusted them to: IoDrvBase = 3.5.5.0 IoStandard = 3.5.10.0 Also, I am using CODESYS SP12, which I understand is the correct version for DSE M840. My questions If DSEServiceTool shows Status OK and package ACK, but the device still says “No application loaded”, does that mean: the .pkg was transferred but not accepted as a valid application? the package was built incorrectly? the boot application / runtime / firmware versions are still mismatched? What is the correct procedure to generate CodesysApp.pkg for M840-02 V4.1? Is there any known compatibility issue between: DSE CODESYS Package 1.5.44 M840 MKII Firmware 4.1.2 CODESYS 3.5 SP12 Has anyone successfully loaded even a minimal empty test project into M840-001-02, and if so, what exact versions/process did you use? Any help would be appreciated.
Last updated: 2026-03-17
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