Post by hannibal on Codesys Trend - setting Y axis minimum and maximum as variables - error ^{CODESYS Forge talk (Post)}
I am experiencing an issue when trying to define the Y-axis limits in a Trend Graphic using variables. When I set the Minimum and Maximum values as variables, an error is triggered. My goal is to make the Y-axis limits dynamic so they can adjust according to the installation. Both variables are initialized as follows: gP_YMin = -100.0 gP_YMax = 100.0 However, I still get the following error: "The minimum axis value must be less than the maximum axis value" Does anyone have an idea why this is happening or how to resolve it?
Last updated: 2026-03-22

Post by hannibal on Codesys Trend - setting Y axis minimum and maximum as variables - error ^{CODESYS Forge talk (Post)}
I am experiencing an issue when trying to define the Y-axis limits in a Trend Graphic using variables. When I set the Minimum and Maximum values as variables, an error is triggered. My goal is to make the Y-axis limits dynamic so they can adjust according to the installation. Both variables are initialized as follows: gP_YMin = -100.0 gP_YMax = 100.0 However, I still get the following error: "The minimum axis value must be less than the maximum axis value" Does anyone have an idea why this is happening or how to resolve it?
Last updated: 2026-03-22

Post by thierry-b on CODESYS device discovery performance in large networks (/16) ^{CODESYS Forge talk (Post)}
Hello, We are using CODESYS 3.5 SP19.70 in an educational environment with several WAGO PFC200 controllers (CODESYS Runtime). Our campus network is currently configured as a /16, which creates a very large broadcast domain. We observe slow device discovery and long scan times when opening the network view. Before restructuring our architecture, we would like to know the recommended network practices for CODESYS: Recommended broadcast domain size for device discovery Possible impact of large networks (/16) on scan performance Usual recommendations (VLANs, /24 segmentation, etc.) Known limitations or points of attention in extended networks Any guidance or official recommendations would be very helpful. Thank you.
Last updated: 2026-03-29

Post by jorenbeyl on library inside library ^{CODESYS Forge talk (Post)}
I am currently developing a library that contains real‑time data. To handle this real‑time data, I am using additional libraries called SysTime and SysTypes Interfaces. When I compile my library on its own, no errors occur. However, when I use this library in a project and compile the project, I get an error indicating that the SysTime data type is not recognized. This happens even though the SysTime library is visible as a dependency under my library. Does anyone know how to correctly include a library within another library so that the project recognizes the sub‑library without causing compilation errors?
Last updated: 2026-04-23

Post by jroddball79 on PM556-TP-ETH — How to change IP address without overwriting the PLC program? ^{CODESYS Forge talk (Post)}
We have checked open ports. SSH (22) and HTTP (80) are not reachable. The only open ports are: 502 (Modbus TCP — used for lighting control) 1200 (CODESYS runtime) 1201 (CODESYS runtime) We can connect via Automation Builder using the current IP, but we don't have the original project source — only an empty project. This is why we are afraid of doing a full download, as it would overwrite the running application. Is there any way to change the IP through the CODESYS runtime protocol on ports 1200/1201 without affecting the running program?"
Last updated: 2026-05-20

Post by baotthitawat on Cloud SCADA for Industrial Energy Monitoring ^{CODESYS Forge talk (Post)}
Recently I’ve been exploring ATSCADA iEnergy Tools for SCADA-based energy monitoring systems. One thing I find interesting is how modern SCADA platforms are evolving beyond traditional machine monitoring. Many industrial systems are now using Cloud SCADA architectures for centralized energy management, remote dashboards, and operational analytics. ATSCADA iEnergy Tools supports: Real-time energy monitoring Historical data logging MySQL integration Reporting and Excel export Remote SCADA dashboards Cloud-based monitoring systems I think this type of solution is practical for factories, power monitoring applications, building management systems, and other industrial automation projects where energy optimization is becoming increasingly important. Industrial automation is clearly moving toward web-based and cloud-connected SCADA platforms, especially as more facilities focus on digital transformation and smarter energy management
Last updated: 2026-05-26

Post by baotthitawat on Cloud SCADA for Industrial Energy Monitoring ^{CODESYS Forge talk (Post)}
Recently I’ve been exploring ATSCADA iEnergy Tools for SCADA-based energy monitoring systems. One thing I find interesting is how modern SCADA platforms are evolving beyond traditional machine monitoring. Many industrial systems are now using Cloud SCADA architectures for centralized energy management, remote dashboards, and operational analytics. ATSCADA iEnergy Tools supports: Real-time energy monitoring Historical data logging MySQL integration Reporting and Excel export Remote SCADA dashboards Cloud-based monitoring systems I think this type of solution is practical for factories, power monitoring applications, building management systems, and other industrial automation projects where energy optimization is becoming increasingly important. Industrial automation is clearly moving toward web-based and cloud-connected SCADA platforms, especially as more facilities focus on digital transformation and smarter energy management
Last updated: 2026-05-26

Post by alex-n on Problem with keeping up the distance between two axes ^{CODESYS Forge talk (Post)}
Hello. I have a task to synchronize the movement of two axes and maintain the distance between them. First axe makes equal steps by trigger using MC_MoveRelative function. The second one is standstill and after another signal should catch up the first one from its position to a specified distance and keep it. I've tried to use MC_Phasing and mostly it works. Second axis catches up the first and starts make step with it. But in one moment this axis can crash into the first and there is no clear connection as to why this is happening. It can work correct for a day or for a week.
Last updated: 2026-06-04

Post by brouwyka on JSONByteArrayWriter problem? ^{CODESYS Forge talk (Post)}
Hey there! I am currently running into the exact same issue. The JsonData object has all inexes & parent indexes in the way I expect, everything is correctly "linked". It purely seems that the writer is incorrectly parsing said JsonData, not based on parent & child index, but on something else that breaks it and puts things at the root, instead of the specified parent index. Did you ever manage to find a solution, or another way of achieving your JSON composing? I'm currently working on Codesys V3.5 SP19 Patch 7 with IIOT Libraries SL 1.13.0.0, specifically JSON Utilities SL 1.13.0.0 (to send requests to APIs with JSON bodies using Web Client SL 1.13.0.0).
Last updated: 2026-06-08

Post by gseidel on Limit Axis CNC Jerk using SMC_Polynomial_AbsMaxLocs ^{CODESYS Forge talk (Post)}
Dear josepmariarams, this (internal) function has been removed with SoftMotion 4.17.0.0. We do not have public functions to compute the extrema of a polynomial. On which polynomials exactly did you call SMC_Polynomial_AbsMaxLocs? (Maybe if I understand better how you limit the jerk I can come up with an alternative.) There is no functionality to limit the jerk of individual axes in the CNC. With SMC_LimitDynamics, you can limit the velocity and acceleration of cartesian (X/Y/Z) and additional (P/Q/U/V/W/A/B/C) axes, but not the jerk. And with a quadratic ramp type you can limit the jerk on the path. Best regards, Georg
Last updated: 2026-06-10

Post by domebruce on TCP communication and TCP Streams ^{CODESYS Forge talk (Post)}
Hello, I'm doing some tests with TCP communication using Reader, Writer and TCP_Process components from NBS 4.0. I'm having a really hard time finding documentation and examples on these components. I found a very simple and incomplete example here: https://forge.codesys.com/prj/codesys-example/nbs/home/Home/. The documentation is also insufficient: it only provides the names of the FBs, Methods and their parameters, but no descriptions about how to use them. Do you have any suggestions on where to find more support? More generally, why is the free online CoDeSys documentation so poor? What do you think? Thanks Domenico Canavero
Last updated: 2026-06-16

Post by arundara on Variable Sync Issue In Soft Plc Redundancy ^{CODESYS Forge talk (Post)}
Hello, I was trying to create a redundancy POC for our application where we read data from few modbus tcp devices. As there is a limitaion that modbus tcp device support only for single master device, we wanted to test how the variable sync happens in redundancy mode. For that i have used the redundancy sample code added a variable "b" under a condition. What i observed was while active controller is running, if passive controller is powerup, passive controller is able to sync all the data configured for redundacny. But after that the variable data which resided under a condition is not synching from active to passive controller. I have attached the image where i have highlighter the variable. Can some help me to understand how redundacny work in codesys soft plc and if there is a solution to sync variable which are under condition, please explain the same or suggestion to achieve the same. Hardware - Raspberry Pi (2 qty) Redundancy licence used - yes in both controllers. Codesys runtime - 4.9.0.0 Codesys software version - V3.5 SP19 if i have posted this question in wrong section, please do let me know in whcih section i have to post this question.
Last updated: 2023-12-01

Post by ofey on Testing of Codesys program ^{CODESYS Forge talk (Post)}
Hi! I thought to hear what you guys think is the best way to test the program in my scenario. I have some PLC programs that have been made and deployed on different PLC's. The program has added the specific devices and IO that is applicable. I have made a test environment for everything outside of the PLC, ie. the same SCADA system that is talking to the PLC, and a program running locally is simulating the plant (level regulation of different tanks). Pr. now I have had to manually change the variables that are reading/writing values from the IO so they read/write via OPC instead. I also have to change the device tree from the specific PLC rack, to the soft PLC. So I kind of end up with two different programs that I have to maintain. I was just wondering if you believe there is an easier way to do this. So I can have the exactly same program and kind of switch between the soft mode, and the "real" mode.
Last updated: 2023-12-07

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 ahuckphin on Issues with Modbus Slave with Raspberry Pi ^{CODESYS Forge talk (Post)}
I have a DFRobot RS485 temperature & humidity sensor (SEN0438) connected to my Raspberry Pi via a USB to RS485 adapter. I am able to connect and read the sensor data when running a python code locally. However in Codesys, I encounter this error "A bus error has occurred." and "There was no response in time". Could this be because of Modbus Server Channel and Modbus Server Init configuration on my part? Admittedly I am new to Codesys. To get to this stage, I: 1. added some lines to CODESYSControl_User.cfg 2. added "Modbus_COM" in Codesys and set "Serial Port Configuration" under "General" 3. added "Modbus_Master_COM_Port" in Codesys and checked transmission mode is set to "RTU" 4. added "Modbus_Slave_COM_Port" in Codesys and checked server address is set to 1 (also set 1 in my sensor) 5. added 1 channel and 1 init for "Modbus_Slave_COM_Port" under "Modbus Server Channel" and "Modbus Server Init"
Last updated: 2024-07-10

Post by tyronnosaurus on ReceiveWatchdog FB not working on J1939 P2P PGNs ^{CODESYS Forge talk (Post)}
Hi guys. I've got a device that sends a status message over J1939 and a PLC running Codesys to receive it. This message uses a P2P PGN (as opposed to a broadcast PGN). Codesys can only read it if I mark the J1939_ECU as "Local" (see screenshot 1). The message is received correctly, that is not the problem. The problem is detecting if the message stops being received. Local ECUs have no Watchdog checkbox to detect if the message has been received in the last X seconds. In order to implement a watchdog, I've used a ReceiveWatchdog FB. The same code works well for any non-P2P message, but doesn't work for this particular P2P message I'm trying to monitor. Even if I physically disconnect the device, ReceiveWatchdog.xBusy stays True, and ReceiveWatchdog.xError never triggers due to a timeout error. Is there any caveat in the ReceiveWatchdog FB that makes it unable to monitor P2P PGNs in Local J1939_ECUs?
Last updated: 2024-07-11

Post by julianramirez on ModbusFB write update ^{CODESYS Forge talk (Post)}
Hello everyone, I am testing the ModbusFB library tcp server and so far I am able to create holding registers successfully, however, I am trying to identify after each write which registers got updated (i.e. function code, write value). I can even see the var udiNumWriteRequests, which increases with every write. I noticed that there is logging with the LogStatusInfo method. After I call it I am able to read in the console stuff that I want. Nevertheless, this is only available at the logs and is not easy to decode because it consists on several messages, I would like to know if there is a way for me to retrieve this information from the function itself with pointers or if there is any way to copy the logs messages (assuming that I can filter them with the LoggingOptions to only show what I need) inside the runtime code and not in the console. Thanks for your help :)
Last updated: 2024-09-16

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 fabiodasilveira on PLC Shell commands via ST Code ^{CODESYS Forge talk (Post)}
Hello Everybody, I have created a project for an Eaton XC303 that sends lots of data to a router via UDP. It works fine. However, when there is more than one product connected to the router, then it is necessary to change the IP address of the Ethernet port 0, from e.g. 192.168.2.11 to 192.168.2.12 (second product). It is easily done via PLC Shell (setipaddr 0 192.168.2.12), but the people in production is struggling with the PLC Shell commands and I would like to create a Visualization page that will hide that. I used the instruction: eChangeIPResult:= SysSockSetIPAddress(strEthernetPort, strIPAddress); and it works, until the PLC resets. I already read some posts and it appears that I need to stop the Ethernet 0 port and Reconfigure it, but I am really struggling to find the right way to do it. Any help will be much appreciated.
Last updated: 2025-02-28

Post by struccc on The future and proper use of CAA.BOLT, CAA.SEMA,.. ^{CODESYS Forge talk (Post)}
Dear All, Dear CODESYS, I'm curiously following CODESYS transitioning away from the CAA libraries, and I'm mostly in favor of these major changes. Naturally, I'd like to align my current (not end-user) developments accordingly. I'm tracking , reading release notes, ... And want to figure out the future :) Is it possible to hear / read more about the reasons, objectives and scope of these changes? One important element is CAA Types - CAA Types Extern. What is the plan with that? What's the future of CAA.SEMA, CAA.BOLT ? I have never used them (always relied on SysLib*), but they are tempting... Would be useful to have a platform independent "Macro" for this functionality... Is there something in existing or planned ? Are they suitable to be used in low level libraries... For Example IO-Drivers, Components, "to-become system libraries"? CAA.TaskLock, CAA.TaskUnlock ? Well, they don't claim platform independency, so I can't rely on those.... Any up-to-date advise, standard, pattern to follow in new libraries for task and resource locking? Practical set of conditional defines to be used? If this information is not publicly available, can you please send a private message about the proper way to achieve this? I have support agreement, just couldn't get trough with these questions... P.
Last updated: 2025-03-14

Post by razebones on sdo read write codesys 3.5 ^{CODESYS Forge talk (Post)}
ENG For some reason, I can't bind a variable to the data parameter. Also, why does only the sdo_read4 function work for me? I also can't write through sdo_write4. I can only view the received values via sdo_read4. Please help me with this task. Moreover, I tried to write the values through sdo write 4 and for a while the data stopped being written and I overwritten it manually and sdo read4 started working again and at the same time they do not want to work in the main task. RU Я не могу почему то привязать переменную к параметру data. Так же у меня почему работает только функция sdo_read4 так же не могу записать через sdo_write4. Могу только просматривать полученные значения через sdo_read4. Помогите пожалуйста с этой задачей. Причём я попытался записать значения через sdo write 4 и у меня на какое то время перестали записываться данные и перезаписал вручную и sdo read4 начал работать снова и одновременно они не хотят работать в main task.
Last updated: 2025-04-01

Post by mondinmr on Unexpected behavior in cyclic encoder read method during INT overflow (wrap-around) ^{CODESYS Forge talk (Post)}
Hi everyone, I’m investigating a potential issue with a cyclic method we use for reading incremental encoders in our libraries. I’ve come across two implementations that, at first glance, appear to perform the same operation: motionUnit.vlPositionActualValue is UINT due strange encoder type. Version A METHOD PROTECTED cyclicReadField VAR_INST actPosFieldOld: INT; rI: INT; delta: INT; END_VAR rI := TO_INT(motionUnit.vlPositionActualValue); delta := rI - actPosFieldOld; m_actPosRaw := m_actPosRaw + TO_LREAL(delta); actPosFieldOld := rI; IF settings.velocityFeebackMapped THEN m_actVelRaw := TO_LREAL(motionUnit.velocityActualValue); END_IF Version B METHOD PROTECTED cyclicReadField VAR_INST actPosFieldOld: INT; END_VAR m_actPosRaw := m_actPosRaw + TO_LREAL(TO_INT(motionUnit.vlPositionActualValue) - actPosFieldOld); actPosFieldOld := TO_INT(motionUnit.vlPositionActualValue); IF settings.velocityFeebackMapped THEN m_actVelRaw := TO_LREAL(motionUnit.velocityActualValue); END_IF Both use INT and the same delta logic, so they seem equivalent. However, when an overflow (wrap-around) occurs, version A continues correctly as expected, while version B unexpectedly resets to -32768 without a clear reason. Has anyone experienced similar behavior or can shed light on what might be happening here? It almost seems as if the cast to LREAL is being applied before the calculation — but that would be illogical and potentially very dangerous in many situations! Thanks!
Last updated: 2025-05-13

Post by rene-h on ClientFilter used the same Client ID 2 times - Bug? ^{CODESYS Forge talk (Post)}
Hello, like the topic name says, i have a problem on one Visu which i cannot reproduce on another Visu. We filter buttons with input locks and visible items with [CURRENTCLIENTID] on different WebVisu's with different ID's, and one time the itfClient used the same Client ID for 2 Clients, so the Visualization on the first ID was wrong, because that one which connected after did not have the same permissions like the first, so the first one was blocked. We read the Clients with the VisuClientIteration project: //count active clients gCli.iNumberOfClients:=gCli.iNumberOfClients+1; // if client is active write data to global struct IF gCli.iNumberOfClients > 0 THEN gCli.astClientInfo[gCli.iNumberOfClients-1].iClientID:=itfClient.ClientId ; gCli.astClientInfo[gCli.iNumberOfClients-1].stCurrentVisu:=itfClient.CurrentVisuName; gCli.astClientInfo[gCli.iNumberOfClients-1].wsUserName:=itfClient.UserName; gCli.astClientInfo[gCli.iNumberOfClients-1].sIpAddress:=itfClient.GetIPv4Address(); gCli.astClientInfo[gCli.iNumberOfClients-1].ClientType:=itfClient.ClientType; END_IF Runtime from the device: 3.5.19.20 Codesys we use: 3.5.20.10 I added a screenshot where the same ID exists 2 times. Thanks for your answers.
Last updated: 2025-05-14

Post by kuegerls on Programmatically clearing or syncing Data Source Manager cache? ^{CODESYS Forge talk (Post)}
Hi everyone, is there a way to programmatically clear the cache of the Data Source Manager in CODESYS so that variable values are re-synchronized from the OPC UA server (Symbol Configuration with OPCUA features)? Alternatively, is it possible to trigger a manual synchronization of data source variables from within the application code at runtime? Here’s the situation: A variable is first written by the OPC UA client to the server in one state of a state machine and changes to another state – so the initial communication works. Later, the server changes the variable value, but the client does not receive or reflect the updated value, unless the variable is actively written again. I’m looking for a way to force the client (data source manager) to re-read or refresh the variable state from the server, possibly by clearing the internal cache or triggering a sync. Any ideas or suggestions would be greatly appreciated! Thanks!
Last updated: 2025-05-23

Post by erictur on CODESYS Control for Linux ARM SL (32 bit) on Moxa UC-3100 IPC ^{CODESYS Forge talk (Post)}
UC3100 comes with Arm Cortex-A8 1 GHz and belongs to Moxa Industrial Linux 1 (Debian 9) for Arm-based Computers. I tried to install the CODESYS Control for Linux ARM SL (32 bit) on Moxa UC-3100 IPC. Unfortunately, the Third-party requirements: - libc >= 2.27 (required by CodeMeter Runtime) of the CODESYS Control for Linux ARM SL cannot be met on the Debian 9, which comes with glibc 2.24. I read the post by @johnlee (Getting Start with Codesys Control for Linux SL) (https://forge.codesys.com/forge/talk/Runtime/thread/0a515ced3f/). Where he discusses installation of CODESYS Control for Linux ARM SL on Debian 9. There was CODESYS Linux runtime v3.5.14 availble and it was successfully intalled on the Debian 9. However, the CODESYS Store has the oldest version V4.1.0.0 32 bit available. There is no way to find the CODESYS Linux runtime v3.5.14. So is there any work around for this? Or I cannot install the CODESYS Runtime on any of the Moxa IPCs based on the Moxa Industrial Linux 1 (Debian 9)?
Last updated: 2025-07-10

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