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 faceplant on CmpDynamicText unresolved references ^{CODESYS Forge talk (Post)}
Hello! I am new to codesys so I am sorry if this is not the right place to ask this question. I am using codesys V3.5 SP20 Patch 1 + (64-bit) and a Groov EPIC PLC (GRV-EPIC-PR2). I am trying to build and deploy my application to the PLC, but when I log in I get 6 errors (codesys_error.png). It seems that the errors have to do with the CmpDynamicText system library which I have as version 3.5.20.0. I have tried to add CmpDynamicText to the ComponentManager section in the PLC's CODESYSControl.cfg file as described in this forum post and still hit the same error. I noticed that the library is grayed out in the library manager, which I think might be the issue. However I don't remember if it was grayed out before I encountered this issue. Please let me know if I can provide anymore info. Thank you!!!
Last updated: 2024-07-19

Post by wbj0t on System libs and I/O Drivers ^{CODESYS Forge talk (Post)}
Hi everyone. My question about: where I can learn (read or watch) an info about codesys workflow through the system IO libs? I want to know how to implement I/O drivers by my self. In the system libs I see many interfaces, methods etc... But there is no explanation about them, just names of methods and fields of the FBs. I know about this page: https://forge.codesys.com/drv/io-drivers/doc/Generic/ There is so BIG the device description file and not so clear explaining of the attributes and elements, also some elements or attributes missed at it all. Yes, there are code examples on this page, but, so shortly and, for example, code about Modbus drivers is absent. And even if I try to add the IoDrvFB with lib, I get and error, something like: "failed to load IoDrvFB driver". And what about the book of codesys that written by Gary Pratt? Is there information about system libs and drivers in this book more clearly? Thank you :)
Last updated: 2024-02-02

Post by squiggleypuff on RemoteTargetVisu creates Unresolved Reference ^{CODESYS Forge talk (Post)}
I have a project with a Festo CPX-E-CEC-C1-PN PLC (Run-time version 3.5.12.50) that I have been developing on just fine using Codesys V3.5 SP19 Patch 5 (64bit). I am at the stage where I wanted to use the Festo HMI screen, and have added a RemoteTargetVisu object to my application. After adding this object, I am no longer able to log in to the PLC as I get an Unresolved Reference warning for 'USERMGRUSERGETPROPERTY' towards the end of the download process. I was able to find this post (https://forge.codesys.com/forge/talk/Visualization/thread/fc686a6cb2/) where the two possible solutions are to "set the placeholder to emtpy" or update the runtime. Problem is, I don't know how to do either of these things, as I'm still very green in Codesys land. I'd be happy to update the Festo PLC runtime, as that seems like the better option, but have not had any luck in finding a tutorial for this online. If anyone could point me in the right direction I'd appreciate it.
Last updated: 2024-03-19

Post by markushunter on Different behavior between the "Start" button in the IDE and the Cmp function "AppStartApplication()" ^{CODESYS Forge talk (Post)}
In our application with CODESYS V3.5 SP19 Patch 5 and the Soft-PLC Name: CODESYS Control Win V3 x64 Typ: 4096 ID: 0000 0004 Version: 3.5.19.50 the application behaves differently when we start the application via Cmp.AppStartApplication(pApp) than when we press the "Start" button in online mode in the IDE. Unfortunately, it looks like the AppStartApplication() function, which is called in the "StopDone" system event, is not able to restart the fieldbus driver correctly, in our case the EtherNet_IP_Scanner: Name: EtherNet/IP Scanner Hersteller: 3S - Smart Software Solutions GmbH Kategorien: EtherNet/IP Scanner Typ: 100 ID: 0000 100B Version: 4.5.1.0 Bestellnummer: 1 And one EtherNet/IP adapter Name: FANUC Robot R30iB Plus Hersteller: FANUC Robotics America Kategorien: EtherNet/IP Remote Adapter Typ: 101 ID: 356_12_4_3 Version: Major Revision=16#3, Minor Revision = 16#1 Beschreibung: EtherNet/IP Target imported from EDS File: fanucrobot0301_r30ibp.eds Device: FANUC Robot R30iB Plus Version Konfiguration 3.5.6.0 The application was cold reset in both cases via CmpApp.AppReset(pApp := pApp, usResetOption := CmpApp.RTS_RESET_COLD. Does anyone know the difference between the functions or services executed by the "START" button in online mode and Cmp.AppStartApplication()? Thanks and best regards, markushunter
Last updated: 2024-03-20

Post by markushunter on Different behavior between the "Start" button in the IDE and the Cmp function "AppStartApplication()" ^{CODESYS Forge talk (Post)}
In our application with CODESYS V3.5 SP19 Patch 5 and the Soft-PLC Name: CODESYS Control Win V3 x64 Typ: 4096 ID: 0000 0004 Version: 3.5.19.50 the application behaves differently when we start the application via CmpApp.AppStartApplication(pApp) than when we press the "Start" button in online mode in the IDE. Unfortunately, it looks like the AppStartApplication() function, which is called in the "StopDone" system event, is not able to restart the fieldbus driver correctly, in our case the EtherNet_IP_Scanner: Name: EtherNet/IP Scanner Hersteller: 3S - Smart Software Solutions GmbH Kategorien: EtherNet/IP Scanner Typ: 100 ID: 0000 100B Version: 4.5.1.0 Bestellnummer: 1 And one EtherNet/IP adapter Name: FANUC Robot R30iB Plus Hersteller: FANUC Robotics America Kategorien: EtherNet/IP Remote Adapter Typ: 101 ID: 356_12_4_3 Version: Major Revision=16#3, Minor Revision = 16#1 Beschreibung: EtherNet/IP Target imported from EDS File: fanucrobot0301_r30ibp.eds Device: FANUC Robot R30iB Plus Version Konfiguration 3.5.6.0 The application was cold reset in both cases via CmpApp.AppReset(pApp := pApp, usResetOption := CmpApp.RTS_RESET_COLD. Does anyone know the difference between the functions or services executed by the "START" button in online mode and Cmp.AppStartApplication()? Thanks and best regards, markushunter
Last updated: 2024-03-20

Post by markushunter on Different behavior between the "Start" button in the IDE and the Cmp function "AppStartApplication()" ^{CODESYS Forge talk (Post)}
In our application with CODESYS V3.5 SP19 Patch 5 and the Soft-PLC Name: CODESYS Control Win V3 x64 Typ: 4096 ID: 0000 0004 Version: 3.5.19.50 the application behaves differently when we start the application via Cmp.AppStartApplication(pApp) than when we press the "Start" button in online mode in the IDE. Unfortunately, it looks like the AppStartApplication() function, which is called in the "StopDone" system event, is not able to restart the fieldbus driver correctly, in our case the EtherNet_IP_Scanner: Name: EtherNet/IP Scanner Hersteller: 3S - Smart Software Solutions GmbH Kategorien: EtherNet/IP Scanner Typ: 100 ID: 0000 100B Version: 4.5.1.0 Bestellnummer: 1 And one EtherNet/IP adapter Name: FANUC Robot R30iB Plus Hersteller: FANUC Robotics America Kategorien: EtherNet/IP Remote Adapter Typ: 101 ID: 356_12_4_3 Version: Major Revision=16#3, Minor Revision = 16#1 Beschreibung: EtherNet/IP Target imported from EDS File: fanucrobot0301_r30ibp.eds Device: FANUC Robot R30iB Plus Version Konfiguration 3.5.6.0 The application was cold reset in both cases via CmpApp.AppReset(pApp := pApp, usResetOption := CmpApp.RTS_RESET_COLD. Does anyone know the difference between the functions or services executed by the "START" button in online mode and Cmp.AppStartApplication()? Thanks and best regards, markushunter
Last updated: 2024-03-20

Post by reinier-geers on License problem gateway ^{CODESYS Forge talk (Post)}
The hole setup is made by 3s. So its a comination of one not two. If Epis decide not to support extra licence whats then the funtion of providing an option with a single license ?? So the idee by 3s has a flod. Epis change the system to add the Stick. I send controller inc stick to Epis. On my software i can see the stick. An then you tel me i need a other license to use an license ?? Makes completly no sense. Codesys should be flexible but is not. I tried Delta. But has no HMI and has its own Codesys ?? Why ?? Then i tried Crist. The block there own system by a password. But dont know the password and cant switch it off. At the end the want me to pay for support to solve ther own made problem. So i send it al back. The extra license is adviced by 3s . Now a few month later still no working solution.
Last updated: 2024-05-01

Post by andrea199403 on Assigning Modbus addresses to a structure in a dynamic way ^{CODESYS Forge talk (Post)}
Hello everyone, I am new to this forum and I am also new to Codesys programming. My problem is this: I have a STRUCT of 64 bool and 30 real, this STRUCT is assigned in the programme 9 times. Now I need to communicate with an HMI via Modbus and I have defined the slave device and created the holding registers for communication. I would like to declare the first call of the STRUCT on the Modbus registers %QX2000.0 to %QX2007.7 for the booleans and on the registers %QW1004 to %QW1034 for the real registers. That said, I would like to change an index and set an offset of 100 bytes for the calls of the other 8 assignments, so that the result is: %QX2100.0 to %QX2107.7 for the booleans and on the %QW1104 to %QW1134 registers for the Real registers, etc. Is there a way to declare this? Thank you very much.
Last updated: 2025-10-21

Post by mil581 on Modbus TCP Server connection is ESTABLISHED but all holding registers are value 0? ^{CODESYS Forge talk (Post)}
Hello everyone! I'm facing a weird issue with CODESYS Control Win V3 x64 on a fresh Windows install. The situation is as follows: CODESYS Modbus TCP Server (Slave) is running and I can see live values in the mapping display of Modbus settings: GVL (e.g., 32, 42, 50). Port 502 is LISTENING according to netstat. When connecting via Modbus Poll or Node-RED, the connection status changes to ESTABLISHED and everything reports as fine. The Problem: Despite the successful connection, all holding registers return 0 no matter what. It's like the OS accepts the TCP handshake, the request counter goes up but the data payload never reaches Modbus Client (in this case Node-RED or Modbus Poll). Quick Stats: Firewall: Completely OFF. Unit ID: Verified & Matching. IP: Tried 127.0.0.1 and 192.168.0.1. Interface: Correctly bound in Ethernet Device settings. I already tried absolutely everything from changing IP address, subnet, port, deleting the project and starting new one and even nuking my old Windows install. Since I am near completion of my bachelor thesis only thing left for me to do is connect SoftPLC to NodeRED via Modbus but this issue is driving me crazy for weeks. I do not know what to do anymore.
Last updated: 2025-12-25

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 russells on Codesys ControlWinV3x64 with EtherCat Slave ^{CODESYS Forge talk (Post)}
Hi there I am running Codesys ControlWinV3x64 (Patch 4) on my laptop for demonstration purposes but I am unable to get connection to the EtherCAT master and slave device. This is the process that I have followed: * Installed NPCap. * Added the xml file for the SMC slave device to the Device Repository. * Activated Control Win SysTray x64 and selected Start PLC. * Scanned the network for the local device (my laptop). * Added an EtherCAT master to the project and scanned the EtherCAT master for the Network and then selected the correct network. * Selected "Scan for devices" to identify the connected I/O. * Add the SMC EtherCAT slave manually because I was unable to scan it in. * Selected "Scan for devices". I have followed the steps described above but I can't scan in the EtherCAT slave or connect to it. I thought this situation was unique to the EtherCAT slave but I have also tried the same for an EtherNet/IP slave using the Ethernet Adaptor and EtherNet/IP scanner and I am also unable to scan in the device or activate the EtherNet/IP network. Any assistance will be appreciated.
Last updated: 2026-02-04

Post by paulpotat on cm4 runtime problem ^{CODESYS Forge talk (Post)}
Hello, I have exactly the same issue, with the following configuration : Hardware version >>> cat /proc/cpuinfo processor : 0 model name : ARMv7 Processor rev 3 (v7l) BogoMIPS : 108.00 Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xd08 CPU revision : 3 processor : 1 model name : ARMv7 Processor rev 3 (v7l) BogoMIPS : 108.00 Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xd08 CPU revision : 3 processor : 2 model name : ARMv7 Processor rev 3 (v7l) BogoMIPS : 108.00 Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xd08 CPU revision : 3 processor : 3 model name : ARMv7 Processor rev 3 (v7l) BogoMIPS : 108.00 Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xd08 CPU revision : 3 Hardware : BCM2711 Revision : a03141 Serial : 10000000d5be5b5f Model : Raspberry Pi Compute Module 4 Rev 1.1 Kernel version >>> uname -a Linux raspberrypi 6.1.21-v7l+ #1642 SMP Mon Apr 3 17:22:30 BST 2023 armv7l GNU/Linux OS Version >>> cat /etc/os-release PRETTY_NAME="Raspbian GNU/Linux 11 (bullseye)" NAME="Raspbian GNU/Linux" VERSION_ID="11" VERSION="11 (bullseye)" VERSION_CODENAME=bullseye ID=raspbian ID_LIKE=debian HOME_URL="http://www.raspbian.org/" SUPPORT_URL="http://www.raspbian.org/RaspbianForums" BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs" /boot/config.txt I added the following line : arm_64bit=0 CodeSys runtime version 4.10 Were you able to solve the issue @michelebianchi ? Any help with this would be appreciated... BR
Last updated: 2024-08-28

Post by otbeka on CAA File Handling: "Read only" error ^{CODESYS Forge talk (Post)}
Hi, On CODESYS V3.5.19.50 I am using the latest 3S File Access library (CAA File & CAA Types) to save and retrieve configuration data from the User Data section of an SD card, via file called config.txt. The application reads the file to memory once upon initialisation, and then the only other operation is overwriting the file with the updated configuration whenever the user changes the settings. An issue is ocurring, seemingly randomly, where the config.txt file, and all surrounding directories, cannot be written to by the unit, returning a READ_ONLY_CAA error upon file open. This sometimes does not clear even after power-cycling the PLC several times, yet checking the file permissions with ls -l shows normal read, write, and execute access. I am wondering if this is caused by the PLC itself or by an issue in my application. I have included my CAA File handler function block (SD_Card_Bin(FB).txt) and any associated types/calls below: TYPE ConfigData : STRUCT Config : ARRAY[0..256] OF STRING(64); NumberOfStrings : UDINT; END_STRUCT END_TYPE TYPE Buffer : STRUCT Data : ARRAY[0..SIZEOF(ConfigData)] OF BYTE; DataLength : UDINT; END_STRUCT END_TYPE A case within my MAIN PRG: mode.WriteConfigDataToFile: VisuElems.CURRENTVISU := 'Screen_Write'; IF xModeHasChanged THEN iErrorCount := 0; iRoute := 0; END_IF CASE iRoute OF 0: inBuffer := ConfigData_To_Buffer(GVL.UnitData); xConfigError := FALSE; xDataConfigured := FALSE; iRoute := 1; 1 : //Read Data from Card SD_Card_Bin.strFileName :=FileName; SD_Card_Bin.iFileOperation := 2; SD_Card_Bin(xExecute :=TRUE, WriteBuffer := inBuffer, xDone =>xDataConfigured, xError=>xConfigError, strErrorCodes=>strError); IF xDataConfigured THEN SD_Card_Bin(xExecute :=FALSE); IF xConfigError THEN iRoute := 32767; ELSE iRoute :=100; END_IF END_IF 100: // The end bCurMode := mode.DisplayProcessVariables; 32767: // Config error iErrorCount := iErrorCount + 1; IF iErrorCount > 2 THEN // Repeats 3 times, if no progress abandons and returns error bCurMode := mode.WriteError; ELSE iRoute := 0; // Try again END_IF END_CASE I'd like to rule out my application as the cause of this bug - help via comments or criticism would be greatly appreciated.
Last updated: 2025-03-19

Post by xcqt on Oop best practice ^{CODESYS Forge talk (Post)}
Hi all, I’m currently trying to improve my OOP structure in CODESYS and I’m looking for some input on how others approach this. I understand the basics like inheritance, interfaces, abstract FBs, methods, and properties, but I still struggle a bit with the overall architecture and what’s considered clean or scalable in bigger projects. As an example, I’m working on two different energy meter function blocks: FB_EnergyMeter_MQTT reads data from MQTT (strings) FB_EnergyMeter_Modbus reads data from Modbus (words) Both have their own Update() method and implement the same interface (something like IF_EnergyMeter). Later on, I’ll probably add more meter types, but they should all behave the same from the controller’s point of view. Now, there’s a FB_GridControl block that needs power data from these meters. I see two options here: Define the meter blocks inside FB_GridControl and call them directly (for example fbModbusMeter.UpdateModbus()). Keep the meter blocks outside and pass them into FB_GridControl as interface references, so the control block doesn’t know which specific type of meter it’s dealing with. Option 2 feels cleaner and more flexible to me, but I’m not entirely sure how to handle the data flow in that case. Should I pass the meter instance through an interface reference (REFERENCE TO IF_EnergyMeter)? Or is there a better way to link the external FBs to the control block? I’d like to hear how you structure this kind of setup or see an example from someone who has done something similar. EDIT: I think i need to do something like this fbModbusUpdateInput(wInput:= wWordValue); fbMqttUpdateInput(strInput:= strStringValue); IF bUseMqtt THEN Meter REF = fbMqttUpdateInput; ELSE Meter REF = fbModbusUpdateInput; END_IF fbControl.SetMeter(UsedMeter := Meter); Or am i thinking wrong? Thanks, Thomas
Last updated: 2025-10-16

Post by dclements on Feature Request: Read-Only References / Pointer-to-Const Support ^{CODESYS Forge talk (Post)}
I would like to suggest adding support for persistent read-only references or pointers in CODESYS, similar to a C++ pointer-to-const (const T*). For example, something conceptually similar to: POINTER TO CONSTANT ST_MyData or REFERENCE TO CONSTANT ST_MyData The important distinction is that the reference itself may still be passed around or reassigned, but the referenced object cannot be modified through that reference. CODESYS currently supports VAR_IN_OUT CONSTANT, which provides read-only reference semantics for parameters, but there does not appear to be an equivalent type that can be stored in a variable or returned from a method. A practical use case is a registry that owns long-lived definitions. The registry needs to retain ownership of the data while downstream systems maintain persistent references to it. Currently, the main options are: Return the struct by value, which loses reference semantics and requires a copy. Return POINTER TO ST_Definition, which allows consumers to modify registry-owned data. Convert the structure into a Function Block and expose a getter-only interface, which provides the desired encapsulation but introduces more complexity and memory overhead. A read-only reference/pointer type would allow libraries to expose persistent, zero-copy access to internally owned data while preserving encapsulation. This would be particularly useful for library APIs and object-oriented CODESYS architectures where ownership of data should remain with one component while other components are allowed to observe it. Similar requests for constant references/pointers have been discussed on CODESYS Forge previously, so this appears to be a recurring use case rather than something specific to one application.
Last updated: 6 days ago

Post by mubeta on Strange problem with the ‘MC_SetPosition’ function ^{CODESYS Forge talk (Post)}
How are the servo drives controlled? EtherCAT, step/dir pulses, other? CANOpen, 1 Mb/s, bus load 35%, cycle time 2ms. Another thought is that - if it's step/dir pulse based control - the pulses from the PLC to the drive are getting missed/lost at high frequencies? If that's the case then there would be multiple troubleshooting steps/corrections that could be investigated. Here, it seems to me that we are getting completely off track with the observed problem. You could try to create a simplified program I had already written this elsewhere. The program before being brought into machines was exhaustively tested in SW emulation and the problem did not occur. However, in emulation I was interested in checking other aspects of the process, not this specific one which is for real a correction made necessary after the fact. The part of the program that does this correction with the function mentioned in the topic, came up from its origins, but I didn't know or didn't think it was really useful. A scruple that later turned out to be necessary. However, for now I do not think I will spend any more time on this verification, already lacking any to do my normal. I remain amazed, however, that a function intended to correct the axis position with the motor in motion and that it should not interfere with this, in fact instead changes behavior as the motor speed changes. Mah! When you manually control the motor directly from the servo drive software at the speeds you are calling for, does it move precisely to the target position? The drive and motor have been working fine for about 10 years. In replacing the machine control system, I opted for CoDeSys where before there was something else. But this is not the subject of the problem. What I need to resolve is the fact that a clutch specially placed at a certain point can slip and, therefore, I have the undeniable need to phase the 'prime mover' to the mechanical position of the machine, detected by a cam for each turn, in order to properly stop at its optimum point. Which for now I have ruled out doing. In fact, if I really have to say, since we have now gone brutally OT, I originally thought that this clutch should only come into action in cases of extreme necessity, as happens in most trials. But this one, the way it is made, slips more easily than I could estimate and the servo-controlled 'prime mover,' and the machine, get out of phase, maybe by a little, but frequently, and when the machine work at it's high speed, (in fact all of the time), I can't adjust properly the 'prime mover' position at fly.
Last updated: 2025-01-18

Post by gustavocsw on MQTT memory leak problem ^{CODESYS Forge talk (Post)}
Hello everyone, I'm using the IoT Library to implement the MQTT communication with my local broker server in order to publish and subscribe at specifics topics to share and consume information about my application. But, it seems that are occurring some memory leak problem in a "high" frequency (more than 10 Hz) subscribe process. I follow the same method as in IoT Lib exemples, and at first looks perfect but my PLC was rebooting frequently and when I check its memory usage that was increasing as fast as the subscribe massage was sent. I'm using a WEG PLC410 and a WEG PLC500, and this error occurred in both of them (including in CODESYS Control Win x64). The application sends to the system a message JSON with the float payload Ex. {"data" : 0.8500}, but this happens with a INT, or BOL as well. I use the follow code in my application to find the value: //FindFirstValueByKey VARs PROGRAM JSON_VELO VAR //------Setting the JSON Subscriber to Set the Relay Value jsonDataVelo : JSON.JSONData; jsonByteArrayReaderVelo : JSON.JSONByteArrayReader; xST1okVelo : BOOL; FindFirstValueByKeyVelo : JSON.FindFirstValueByKey; jsonElementVelo : JSON.JSONElement; xDoneReaderVelo : BOOL; xDoneFindVelo : BOOL; //STRING and WSTRING for Subscribe the massage sPayloadJsonVelo : STRING := 'opa'; psPayloadJsonVelo : POINTER TO BYTE := ADR(sPayloadJsonVelo); //wsPayloadJsonRelaySet : WSTRING := "opa"; wsPayloadJsonVelo : WSTRING := STRING_TO_WSTRING('opa'); pwsPayloadJsonVelo : POINTER TO WORD := ADR(wsPayloadJsonVelo); lrVelo : LREAL; xKeepAliveVelo : BOOL; xSetVelo : BOOL; RSSet : RS; LIMPAR : STRING; //Find the msg end sFindVelo : STRING := '}'; psFindVelo : POINTER TO STRING := ADR(sFindVelo); iLenVelo : INT; iSizeVelo : INT := 12; udiContMsg : UDINT; END_VAR // FindFirstValueByKey CODE // Relay Set configuration xSetVelo := MQTT_SUBSCRIBER.RSVelo.Q1; IF xSetVelo THEN xKeepAliveVelo := TRUE; END_IF IF xKeepAliveVelo THEN udiContMsg := udiContMsg + 1; iLenVelo := TO_INT(StrLenA(psPayloadJsonVelo)); iSizeVelo := iLenVelo - TO_INT(MQTT_SUBSCRIBER.udiPayloadSizeVelo); StrDeleteA(psPayloadJsonVelo,iSizeVelo,iLenVelo); wsPayloadJsonVelo := STRING_TO_WSTRING(sPayloadJsonVelo); pwsPayloadJsonVelo := ADR(wsPayloadJsonVelo); //MQTT.ConvertUTF8toUTF16(sourceStart:= ADR(sPayloadJsonVelo), targetStart:= ADR(wsPayloadJsonVelo), dwTargetBufferSize:= TAM, bStrictConversion:= 1); //Reset jsonByteArrayReader jsonByteArrayReaderVelo ( xExecute := TRUE, pwData := pwsPayloadJsonVelo, jsonData := jsonDataVelo, xDone => xDoneReaderVelo ); FindFirstValueByKeyVelo( xExecute := xDoneReaderVelo, wsKey := "data", diStartIndex:= 0, jsonData := jsonDataVelo, jsonElement => jsonElementVelo, xDone => xDoneFindVelo ); IF xDoneFindVelo THEN lrVelo := jsonElementVelo.value.lrValue; //Reset jsonByteArrayReader jsonByteArrayReaderVelo ( xExecute := FALSE, pwData := pwsPayloadJsonVelo, jsonData := jsonDataVelo, xDone => xDoneReaderVelo ); FindFirstValueByKeyVelo( xExecute := FALSE, wsKey := "data", diStartIndex:= 1, jsonData := jsonDataVelo, jsonElement => jsonElementVelo, xDone => xDoneFindVelo ); xKeepAliveVelo := FALSE; GVL.xSetVeloRead := TRUE; END_IF END_IF And this to subscribe at the topic: //SUBSCRIBE VAR: //----------------- Subscribe Velocity ----------------------- MQTTSubscribeVelo : MQTT.MQTTSubscribe;//Variable MQTTSubscriber block -X - function-X wsTopicSubscribeVelo : WSTRING(1024) := "CORE/odometry/GET/data/simp"; // Topic to publish a message sSubscribeMassageVelo : STRING; udiPayloadSizeVelo : UDINT; xSDoneVelo : BOOL; xSErrorVelo : BOOL; xReceiveVelo : BOOL; eSTypeVelo : MQTT.MQTT_ERROR; eSMQTTErrorVelo : MQTT.MQTT_ERROR; RSVelo : RS; udiCont : UDINT; //SUBSCRIBE CODE: MQTTSubscribeVelo( xEnable:= MQTT_CLIENT.xConnection_Broker AND NOT xSErrorVelo AND NOT JSON_VELO.xKeepAliveVelo, pbPayload:= JSON_VELO.psPayloadJsonVelo, udiMaxPayloadSize:= SIZEOF(JSON_VELO.sPayloadJsonVelo), udiPayloadSize => udiPayloadSizeVelo, mqttClient:= MQTT_CLIENT.ClientMQTT, wsTopicFilter:=wsTopicSubscribeVelo, xDone => xSDoneVelo, xError=> xSErrorVelo, xReceived => xReceiveVelo, eMQTTError=> eSMQTTErrorVelo ); RSVelo(SET := xReceiveVelo, RESET1 := JSON_VELO.xKeepAliveVelo);
Last updated: 2024-09-09

Post by ofey on EtherCAT fieldbus ^{CODESYS Forge talk (Post)}
Hi, everyone! I'm trying to set up a PLC controller and a connection to an EtherCAT slave device in Codesys. I want to create a flexible program that I can upload to multiple controllers with different remote IO connected (same program). On one plant i may have 5 AI-cards and 3 DO-cards, and on another I may have 4 AI-cards and 2 DO-cards. For not needing to maintain several different programs wih different devices defined in the program (one for each set up) I thought that using a remote IO would make it easier having a single program. That way I could refer to different memory addresses instead of predefined slots/channels and IO's, that would give me errors if there was a different IO on the plant than what the program expected. When I tried setting up the etherCAT master, I saw that I had to define the etherCAT slave devices with the different IO'cards for me to be able to refer to the memory addresses in a PRG. Exactly what I was trying to avoid. My setup is something like a program that can handle 16 separate pump controls. In a year maybe 6 plans get deployed, and depending on how large the project is, the number of pumps can vary between 4 and 16. And the managers dont want to have IO's for all 16 pumps on every cabinet, and I dont want to maintain 16 separate projects files in case of updates etc. I thought the best way to tackle this was having a single project that read/write data to the different pump IO's by remote IO (fieldbus ethercat) addresses. And the number of pump controls are activated by an external GUI. If pump 1-6 is activated by the GUI, then the PLC-program tries to read/write input/outputs from predefined addresses for the expected IO's. My test setup is a PFC200 WAGO controller and a EtherCAT fieldbus coupler (750-354) with some IO. I hope I didn't explain this too horrible, and if there is a more easy and elegant solution for this challenge I appreciate a feedback on this.
Last updated: 2024-04-08

Post by mariapaola on Port instantiation of serial interface in WAGO PLC using Modb_L05.lib in CoDeSys v2.3 ^{CODESYS Forge talk (Post)}
Hi, Would really appreciate your insights in this issue I have. I am currently using a WAGO 750-881 with multiple IO devices. For one of them I already occupied the MODBUS Master configuration tool so I cannot overwrite it for my other devices. I have a total of two serial interfaces WAGO 750-652. The first one is instantiated in COM2 and doesn't need any protocol since the information comes in an specific formatting that need little code to differentiate between needed info. This one is working just fine. The second one is where I have an issue. I have tried to instantiate the port using MODBUS library modb_L05.lib to properly receive the data from an ARDUINO and I am absolutely unable to open the port: Signal DEVICE2.fbModbus.MODBUS_EXT_MASTER.Interface.Com_Port_Ist_Offen is never TRUE, among with all other signals from that interface, while signal DEVICE1.COM2.Com_Port_Ist_Offen is TRUE, and the other signals also read as TRUE or FALSE. I have tried instantiating the second one as the first one, changing COM3 to COM4, I've tried a lot of things but it wont ever open the channel. I don't know if you have any recommendations for me. For both physical modules, both witness LEDs A and E are on. First one is instantiated like this: PROGRAM DEVICE1 VAR wBaudRate : WORD := BAUD_9600; bDataBits : BYTE := 8; bParity : BYTE := 0; bFlowControl : BYTE := 3; (RS422 FullDuplex with continous send) i : INT; COM2 : SERIAL_INTERFACE; xOpenPort2 : BOOL := TRUE; ( Flag to open the Port ) xInitPort2 : BOOL; ( Flag to initiallize the Port ) ReceiveBuffer2 : typRing_Buffer; END_VAR COM2( bCOM_PORT_NR := 2, cbBAUDRATE := wBaudRate, cbsBYTESIZE := bDataBits, cpPARITY := bParity, csSTOPBITS := STOPBITS_1, cfFLOW_CONTROL := bFlowControl, utRECEIVE_BUFFER := ReceiveBuffer2, ptSEND_BUFFER := ADR(SendString2), xINIT := xInitPort2, xOPEN_COM_PORT := xOpenPort2, iBYTES_TO_SEND := LEN(SendString2)+1, xSTART_SEND := xSendActive2 ); Second one like this: PROGRAM DEVICE2 VAR COM4 : SERIAL_INTERFACE; xInitPort4 : BOOL := TRUE; xOpenPort4 : BOOL := TRUE; ReceiveBuffer4 : typRing_Buffer; fbModbus : MODBUS_EXTENDED_MASTER_RTU; fbError : enumMB_ERROR; stQuery : typModbusExtendedQuery; stResponse : typModbusResponse; au16Data : ARRAY[0..14] OF WORD; i : INT; tPoll : TON; END_VAR COM4( bCOM_PORT_NR := 4, cbBAUDRATE := BAUD_9600, cbsBYTESIZE := 8, cpPARITY := 0, csSTOPBITS := STOPBITS_1, cfFLOW_CONTROL := 2, ( RS-485 half-duplex ) utRECEIVE_BUFFER := ReceiveBuffer4, xINIT := xInitPort4, xOPEN_COM_PORT := xOpenPort4, xSTART_SEND := xSendActive4, ); stQuery.SlaveAddress := 1; stQuery.FunctionCode := 3; stQuery.Read_StartAddress := 0; stQuery.Read_Quantity := 15; (Poll code) fbModbus( ENABLE := TRUE, bCOM_PORT := 4, ( COM4=> 750-652 port ) cbCOM_BAUDRATE := BAUD_9600, cpCOM_PARITY := 0, csCOM_STOPBITS := 1, cbsCOM_BYTESIZE := 8, cfCOM_FLOW_CONTROL := 2, TimeOut := T#500ms, StartFunction := xStart, ExtQuery := stQuery, Response := stResponse, MB_Error => fbError ); FOR i := 0 TO 14 DO au16Data[i] := stResponse.Data[i]; END_FOR;
Last updated: 2025-11-28

Post by camilloo on Control for Linux SL on Ubuntu Core ^{CODESYS Forge talk (Post)}
(dhumphries) I followed your advice and tried it on Ubuntu Server. Was a good choice. Your material was also very helpful :). Thanks for Your help! I no longer have problems connecting to Ubuntu. However, I still cannot install Virtual PLC. I'm currently getting a missing path message: "C:\Program Files\CODESYS 3.5.19.60\CODESYS\CODESYS Virtual Control for Linux SL\Delivery\virtuallinux\VirtualControlAPI.py." It looks as the package: "CODESYS Virtual Control for Linux SL" was not installed. But, there isn't one in CODESYS Store or I'm doing something incorrectly.
Last updated: 2024-03-03

Post by miodusy on CODESYS Control Standard S and Beaglebone ^{CODESYS Forge talk (Post)}
Hi, CODESYS Control Standard S + CODESYS Visualization L, CODESYS Control for Beaglebone 4.11.0.0, CODESYS V3.5 SP20 + (64-bit) I have problem that license manager say that this device is not supported when i try active whole license. When I select only runtime and communication it is go next step, but then I no have license on in Visualistion section, all of rest of software metric licese is ok(IO, Istances of com et, code size etc.). Thanks!
Last updated: 2024-05-11

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 martinlithlith on Device User Logon and No device is responding.. Pi4b codesys 3.5 SP19 2 + (64-bit) ^{CODESYS Forge talk (Post)}
Hi! Im slowly starting to loose it and i need som help! After a few night of reading up and testing i´m still stuck as a rock and you guys and girls are my last resort for this project. Basic facts; Win 11 Codesys 3.5 SP19 2 + (64-bit) Raspberry pi 4 model b 2 gb Raspian release 11 aarch64 What keeps me up late at night; Username and Password when trying to connect to device and device only beeing connectable for a few seconds. Some of the things I have tried; Username and passord; Credientials from the raspberry Administrator Administrator admin admin Admin Admin administrator administrator Usernames and passwords that I sometimes use (this was a longshot i know, but i was running out of ideas and energy). :) Epand filesystem, activating i2c, spi, 1-wire I can start the gateway and start the runtime. I cant install the edgearm64, arm64 runtime package eventhough I guess i should, i get code [ERROR] Error output: dpkg: error processing archive /tmp/codesysedge_edgearm64_4.8.0.0_arm64.deb (--install): [ERROR] Error output: package architecture (arm64) does not match system (armhf) [ERROR] Error output: Errors were encountered while processing: [ERROR] Error output: /tmp/codesysedge_edgearm64_4.8.0.0_arm64.deb code as a respons. I have tried to Reset Origin Device - no change. I have tried to remove the /etc/CODESYSControl_User.cfg [CmpUserMgr] but i could not find it and i was not sure if i should add it instead but i did not want to mess somthing up. I have tried to create a second gateway with the specific ip if the pi, that did not help. Could it be that i´m currently connected to the pi through WIFI? I can ping the pi and I can connect and control it through VNC. When i scan to select gateway target (scan edge gateway) i find 17-21 devices but can find the pi throug the mac adress. I started of trying to use the "CODESYS Control for Raspberry Pi SL" (I have a license sience earlier) as i read somewhere that this could be used on a Pi4 as well but now i´m trying with the MC SL, no changes, same problem. Right now - gateway version 4.8.0.0 (edgearmHF, armhf), Runtime Package 4.5.0.0 (raspberry, armhf). Any sugestions are very welcome! As mentioned above, theese are some of the things that i have tried/done - but i have been going at this for a while. Best, Martin
Last updated: 2023-09-10

Post by solidlogicguy on Little endian to Float from Modbus RTU ^{CODESYS Forge talk (Post)}
Hello, I got a device from which I require to read values from I am using a WAGO PLC 750-8212 and I am communicating through Modbus Master FUNCTION BLOCK from library WagoAppPLCModbus in Codesys 3.5 to this device. I already receive data from the device that is a CVM to monitor voltage from a fuel cell. The technical support of the company that makes these devices says that the data is sent in little endian form. And I want to convert it to a float value. The tech support sent me the next instructions of how to do it but I am new using codesys, so any advice or help I will really appreciate so much. Message from tech support: The process is complicated, better to do it with already implemented library in the language/program you use. Basically the process should be next: To convert the two Modbus registers containing parts of a 32-bit float in little-endian byte order to a floating-point number using mathematical operations, you first need to combine the two 16-bit integers (assuming reg1 is the lower word and reg2 is the higher word) and then interpret the result according to the IEEE 754 standard. Given: - Register 192 (reg1) = 4096 - Register 193 (reg2) = 14884 Step 1: Combine the two registers. Since we are dealing with little-endian byte order, reg2 is the high word, and reg1 is the low word: combined = reg2 * 2^16 + reg1 combined = 14884 * 65536 + 4096 combined = 975175680 + 4096 combined = 975179776 Step 2: Convert the combined value to binary: combined_binary = '1110101101011100000000000000000' Step 3: Split the binary into IEEE 754 components: Sign bit (1 bit): 0 Exponent (8 bits): 11101011 Mantissa (23 bits): 01011100000000000000000 Step 4: Convert the binary exponent to decimal and subtract the bias (127 for 32-bit floats): exponent = int('11101011', 2) - 127 exponent = 235 - 127 exponent = 108 Step 5: Calculate the mantissa as a fraction: The mantissa in IEEE 754 format is the fractional part after the leading 1 (which is implicit). Therefore, we need to convert the binary mantissa to decimal and add the implicit leading 1: mantissa_fractional = 1 + int('01011100000000000000000', 2) / 2^23 mantissa_fractional = 1 + 18688 / 8388608 mantissa_fractional = 1 + 0.002227783203125 mantissa_fractional ≈ 1.002227783203125 Step 6: Combine the sign, exponent, and mantissa to get the float value: float_value = (-1)^0 * mantissa_fractional * 2^exponent float_value = 1 * 1.002227783203125 * 2^108 Because the exponent is quite large, the resulting float value is a very large number.
Last updated: 2023-12-15

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