Post by imdatatas on MC_MoveAbsolute: C0138: No matching 'FB_Init' method found for instantiation of SMC_MoveAbsRelPerformerImpl [ERROR]
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Dear @gseidel, Thank you for your reply. The exact version of Codesys and its compiler was 3.5.21.20. The compiler version was fixed and could not be changed in project settings. Since I couldn't continue due to this compilation error, I temporarily overcame this issue as follows. -- I completely uninstalled Codesys 3.5.21.20 and completely deleted the Codesys folder in the C:\ProgramData folder. -- I restarted my computer and installed Codesys 3.5.19.70. -- I updated the Codesys Installer and all its add-ons to the latest versions. -- The project that was giving me the compilation error I mentioned before is now open with Codesys 3.5.19.70, compiled it, and successfully downloaded it on the device. -- I haven't encountered the same problem anymore. I think this issue is related to SP21 and its compiler. Frankly, I'd expect a project created with an older version to compile without errors after opening it with the latest Codesys version and updating all libraries. Regards, imdatatas
Last updated: 2025-09-26
Post by baott569 on CODESYS OPC UA Security: HMI Client Not Receiving Server Certificate
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Hello everyone, I am currently using OPC UA in CODESYS with the security mode BASIC256SHA256 β Signed and Encrypted. The OPC UA Server is running on an RTE CX device, and the HMI is running on another computer. I have reviewed many CODESYS documents and successfully established communication when the security mode is set to None with Anonymous login. However, when security is enabled, the server does not provide its certificate for the CODESYS HMI client to trust. Interestingly, the client can send its certificate to the server, and UAExpert works normally, but the CODESYS HMI client does not receive the server certificate. Can anyone help clarify what I might be missing? I have been stuck on this issue for three days. If I missed or misconfigured any step, please let me know. I believe I am stuck at step 15 in the following CODESYS guide: Encrypting the Communication of a Data Source OPC UA Client https://content.helpme-codesys.com/en/CODESYS%20Communication/_cds_encrypt_communication_data_sources_opc_ua_client.html Thank you very much.
Last updated: 2026-01-06
Post by animesh on SoftPLC (CODESYS Control x86 RTE V3 x64) OPC UA binds only to 127.0.0.1 β Not binding to LAN IP
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Hello everyone, I am facing a persistent issue with the OPC UA Server on Advantech Soft PLC with hard realtime for Win64 (V3_5_2010_3) and need help from the community. Device Information Name: Advantech Control x86 RTE V3 x64 Vendor: Advantech Co., Ltd. Categories: PLCs Version: 3.5.20.10 Description: Advantech Soft PLC with hard realtime for Win64 (V3_5_2010_3) Problem Summary The OPC UA Server works perfectly when accessed via: opc.tcp://localhost:4842 opc.tcp://<hostname>:4842</hostname> But it does NOT work when using the LAN IP: opc.tcp://192.168.0.XX:4842 In UAExpert I get: Discovery FindServers on opc.tcp://192.168.0.XX:4842 failed (BadCommunicationError) Port is LISTENING in windows Firewall.. Tried with turning off the firewall completely. System Information Windows 10 x64 Advantech CODESYS RTE Soft-PLC (hard real-time) Network IP: 192.168.0.XX Hostname: WINDOWS-XXXXX Need your Support
Last updated: 2025-11-24
Post by baott569 on CODESYS OPC UA Security: HMI Client Not Receiving Server Certificate
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Hello everyone, I am currently using OPC UA in CODESYS with the security mode BASIC256SHA256 β Signed and Encrypted. The OPC UA Server is running on an RTE CX device, and the HMI is running on another computer. I have reviewed many CODESYS documents and successfully established communication when the security mode is set to None with Anonymous login. However, when security is enabled, the server does not provide its certificate for the CODESYS HMI client to trust. Interestingly, the client can send its certificate to the server, and UAExpert works normally, but the CODESYS HMI client does not receive the server certificate. Can anyone help clarify what I might be missing? I have been stuck on this issue for three days. If I missed or misconfigured any step, please let me know. I believe I am stuck at step 15 in the following CODESYS guide: Encrypting the Communication of a Data Source OPC UA Client https://content.helpme-codesys.com/en/CODESYS%20Communication/_cds_encrypt_communication_data_sources_opc_ua_client.html Thank you very much.
Last updated: 2026-01-06
Post by risele on Modbus connection via Qronox PCD3 M6893
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You are welcome. Also note, that it's valid only if you modbus-device use same real/float value representation (IEEE 754). That's true for most of systems. But some devices may have other representation, such as integer + position of the decimal point, for example 123.456 is integer = 123456 and position = 3 Also note, that, ones again, depending on endianess of each system, you may also need to swap not just words, but bytes. TYPE u_Real : UNION rVal:REAL; wVal:ARRAY[0..1] OF WORD; bVal:ARRAY[0..3] OF BYTE; dwVAL:DWORD; //same as previous, may be easier to specify the MB register END_UNION END_TYPE than swapping may be something as VAR A,B,C,D:BYTE; //Bytes of the real value uIn, uOut:u_Real; rVal:REAL; ModbusReg1,ModbusReg2:WORD; END_VAR uIn.rVal:=rVal; uOut.A:=uIn.D; uOut.B:=uIn.C; uOut.C:=uIn.B; uOut.D:=uIn.A; ModbusReg1:=uOut.wVal[0]; ModbusReg1:=uOut.wVal[2]; Or you even need to reorder bits... Ones again, sending float/real values is not defined by Modbus protocol itself, so it is hardware- and software-dependent. The Modbus Poll (and most of modbus tools) have configuration parameters that will properly swap bytes on their side. Ones again, that's very helpful: https://www.scadacore.com/tools/programming-calculators/online-hex-converter/
Last updated: 2026-02-19
Post by toby on Ethercat Servo Setup
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Hi Everyone, I have a simple project with a single servo, but its my first time using Codesys and motion, so I'm a little confused and lost, I've tried to read the tutorial online, but I'm not having much luck sorry. Can I please ask for some pointers. I have a ComfilePi HMI (Raspberry Pi) communicating to a Omron R88D-1SN08H-ECT amplifier. Please see the attached project file (which is better for sharing, the project file, or a archive?). This file was simply for testing the motion of the servo before anything else is tested with it. The project simply rotates the servo 1 rotation when called for, but the speed can vary based on user input. Nothing much fancy. As yet, I haven't had any servo movement, no errors on the amplifier display. How do I link the motion FBs to the physical drive? Thank you very much for any help you can offer. I'm sorry if I'm doing something very stupid or basic and getting it wrong. Have a good day. Toby
Last updated: 2023-09-20
Post by riccardo on VisuElems.CurrentUserGroupId is not stable
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GoodMorning everyone. I have a system that, in case of alarm, have to block. When the operator logs in must have to acknoledge the alarm and should operate in the system freely. To perform this I detect the logged User by (VisuElems.CurrentUserGroupID <> 0) with a similar code to the the following: PROGRAM AlarmMngt VAR alarm : BOOL:= FALSE; Ack : BOOL:= TRUE; PushBottonOpening : BOOL:= FALSE; Valve : BOOL := FALSE; Flag: BOOL := FALSE; END_VAR IF alarm AND Ack AND (NOT Flag) THEN valve := FALSE; PushBottonOpening := FALSE; Ack := FALSE flag := TRUE; ELSIF (NOT alarm) AND Ack THEN flag := FALSE; END_IF (* if the system is in alarm but there is a logged operator that acknowledge the alarm the system allows the valve opening.*) IF (VisuElems.CurrentUserGroupID <> 0) AND Ack AND Alarm AND PushBottonOpening THEN Valve := TRUE; ELSIF (VisuElems.CurrentUserGroupID = 0) AND Alarm THEN valve := FALSE; END_IF The problem I have is in the last 5 lines of the code: Even if there is a logged in user, the GroupID variable is subjected to a refresh that cyclically set for an instant it to 0 and this close the valve making difficult to the user to work Now I solved it creating a time hysteresys cycle but it is not a good solution. Someone is able to explane me why the GroupID variable is sobjected to this refresh and how to stabilize to avoiding it? Thank you in advance, Riccardo
Last updated: 2023-11-10
Post by oi18ct on ARM SL Development Board Recommendation
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Hello codesys forum, My company is looking at developing a solution with Codesys ARM SL. The requirements will not tax the capabilities of Codesys. I would like to buy an AMR 7 or 8 Dev Board for experimenting. I am looking for a recommendation as I have minimal experience with Linux. Any input from the forum would be most appreciated as the hardware requirements as provided by Codesys for ARM SL seem pretty minimal (basically a arm7 or 8 with Debian is all). Our needs are small in scale- something like 8 digital inputs, 6 digital outputs, 2 analog inputs and 1 analog output. A small gui will be published via web visualization for external display (no local display). Communications with ModbusTCP and uart/RS485. It may be necessary to access i2c and make c or python calls to some existing code that is pretty small. Something like the EMCraft STM32MP1 SOM Starter Kit or Octavo Systems OSD32MP1-RED development board? Ideally something that has a path to a SoM for production. Kontron appears to have some interesting options too. Just having a hard time deciding where to start. Thanks in advance... LC
Last updated: 2023-11-11
Post by struccc on Bibliothek: floatingpointutils
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The issue s the byte order typically in this case. Can be especially problematic with floating point numbers - even more tricky if transferred with a word based protocol. It is a peasant way to try out the alternatives, dword order can be a-b-c-d, b-a-d-c, c-d-a-b, d-c-b-a where a is the most significant, d is the least significant byte. So all you need is to swap the bytes in your dword, until you get the expected result. If you don't want to mess writing code for this, I'd recommend CAA_Memory library for that: MEM.ReverseBYTEsInDWORD and MEM.ReverseWORDsInDWORD functions would definitively do the trick. Otherwise, can do like this: VAR dwIn : DWORD := 16#11223344; dwOut : DWORD; rOut : REAL; pIN : POINTER TO BYTE; pOUT : POINTER TO BYTE; END_VAR pIN := ADR(dwIn); //pOUt := ADR(dwOut); pOUt := ADR(rOut); pOut[0] := pIN[3]; pOut[1] := pIN[2]; pOut[2] := pIN[1]; pOut[3] := pIN[0]; Ugly, but does the job...
Last updated: 2024-11-19
Post by bertcom on STRING conversions to DWORD
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Good afternoon. I want to communicate with a Domino Industrial Printer using its Codenet protocol. The printer wants a series of Hexadecimal characters with no spaces or '00' characters. Because of that i chose the option to make the prefix and subfix for my code in a string. I have variable data in another string. With a complete program of a lot of CONCAT functions i eventually get the format of code that the printer accepts ( tested it with the hercules tool). Hercules String : 1B4F513030311B7532626C61636B04 The problem is : Codesys adds automatically 'code' to the code to show it is a string. Codesys string : '1B4F513030311B7532626C61636B04' The printer does not understand this. My idea is to convert the string datatype to an LWORD. I have no idea how to do this. I random types in STRING_TO_DWORD, as return i get 0. That didn't worked. Also on internet the explenations around string converting in codesys are very limited. If there in anyone who can explain me how to do it, i would appreciate it a lot ! Thank you!
Last updated: 2025-01-29
Post by pouyavakili on Execute Codesys Tests with python
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Thank you for your input! What I'm ultimately trying to achieve is automated test execution as part of a CI/CD pipeline (e.g. in GitLab or Azure DevOps). For this, I need to: Open a CODESYS project via script Build the project Run the Test Manager tests from a .TestRepository.xml Collect test results (e.g., pass/fail + a report) Exit with a proper return code (for pipeline success/failure) To integrate this into automation, Iβm using the CODESYS scripting engine via Python (headless), but the issue is that the get_testmanager() function isn't available on the project object β even though Test Manager is installed, licensed, and works interactively in the IDE. Are you suggesting that I should: Use the Test Manager GUI to script the logic with its internal scripting language? Or is there a way to launch the Test Manager in headless/scripted mode, while still being able to control things via Python? If there's a supported way to automate tests with the Test Manager using scripting, especially from pipelines or headless environments, Iβd really appreciate any pointers or example workflows. Thanks again!
Last updated: 2025-07-24
Post by willbechel on Errors about PLC configuration in CoDeSYs software
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I saved it as the same project but in a different location. I opened this "new project". I clicked on the "Direct Login from Automation Builder" button. It automatically directed me to CODESYS, where I was able to create the "Create Boot Project" but first I also clicked login again but inside CODESYS keeping the automation builder login online. Additional Information: The "Create Boot Project" function in CODESYS is used to create a project that will automatically start when the controller is booted up. To create a boot project, you must first create a new project in CODESYS. Once you have created a new project, you can then use the "Create Boot Project" function to create a boot application. The "Create Boot Project" function will create a new application that is based on the current project. The new application will be saved in the same location as the current project. You can then download the new application to the controller.
Last updated: 2024-02-01
Post by willbechel on Project Login Problem
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I saved it as the same project but in a different location. I opened this "new project". I clicked on the "Direct Login from Automation Builder" button. It automatically directed me to CODESYS, where I was able to create the "Create Boot Project" but first I also clicked login again but inside CODESYS keeping the automation builder login online. Additional Information: The "Create Boot Project" function in CODESYS is used to create a project that will automatically start when the controller is booted up. To create a boot project, you must first create a new project in CODESYS. Once you have created a new project, you can then use the "Create Boot Project" function to create a boot application. The "Create Boot Project" function will create a new application that is based on the current project. The new application will be saved in the same location as the current project. You can then download the new application to the controller.
Last updated: 2024-02-01
Post by dtamm on How to read string from CharBufferPtr?
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I am trying to implement a mechanism to send alarm SMS. For this, I have created an Alarm Class with a Notification Action which calls a POU. This POU implements IAlarmNotifiable making it selectable in the Alarm Class configuration. IAlarmNotifiable has an Execute method which is called by the alarm class. Now, I want to extract the alarm message of the triggered alarm. The Execute method comes with a VAR_INPUT itfAlarm: AlarmManager.IAlarm which supplies a method called GetMessage. The help text says: Returns the message text, that has been configured for the alarm. The result is a pointer to the buffer, where the message text is stored The type of the result is CharBufferPtr, and at some place I read that it can be interpreted as a pointer to string. But I cannot manage to extract the alarm message, all I get are numbers. I have tried the following: psAlarmText := itfAlarm.GetMessage(__SYSTEM.TYPE_CLASS.TYPE_STRING)^; sAlarmText := TO_STRING( itfAlarm.GetMessage(__SYSTEM.TYPE_CLASS.TYPE_STRING)^ ); So how do I get access to the alarm message as clear text? (In this case, "Larm 1")
Last updated: 2024-02-21
Post by salvadegianluca on How to use TON inside an FB that is instanced within a Visu page
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Hi everyone; I'm building a project in which the drag of the mouse over some controls (or the click event) changes the background color of the control items; this change of color is made with an FB that assignes a color code to the background with MUX command based on the value of an enumerator, this part is perfectly working but, when I'm using a touchpanel instead of a web visu (controlled by a mouse) I get into some issues as it seems that the touch operations are not triggering the MouseEnter and MouseLeave properties as it's done with the mouse.... For this reason I'm trying to add a TON to my FB and, if the enum that changes color remains at the same state for more then 3s I'm automatically resetting it to it's "0" so the item gets back the not selected color. Anyhow it looks like the TON function from library is not working in these FB that are instanced in the various visualizations, as instead they do if I create some instances within the POUS. Anyone has ideas of how to make them work?
Last updated: 2024-04-15
Post by salvadegianluca on How to use TON inside an FB that is instanced within a Visu page
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Hi everyone; I'm building a project in which the drag of the mouse over some controls (or the click event) changes the background color of the control items; this change of color is made with an FB that assignes a color code to the background with MUX command based on the value of an enumerator, this part is perfectly working but, when I'm using a touchpanel instead of a web visu (controlled by a mouse) I get into some issues as it seems that the touch operations are not triggering the MouseEnter and MouseLeave properties as it's done with the mouse.... For this reason I'm trying to add a TON to my FB and, if the enum that changes color remains at the same state for more then 3s I'm automatically resetting it to it's "0" so the item gets back the not selected color. Anyhow it looks like the TON function from library is not working in these FB that are instanced in the various visualizations, as instead they do if I create some instances within the POUS. Anyone has ideas of how to make them work?
Last updated: 2024-04-15
Post by bertus on Can't get SMC_SmoothPath to work
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Hi Georg, thanks for your time. What is the value of D_ANGLE_TOL? It is set to 0.01. Do you need the assignment bAbort := NOT bDecoder? Does it help to leave it out? This seems to make no difference. Any errors (e.g. SMC_SmoothPath.Error/ErrorID) or PLC log messages? No errors or log messages. What if you comment out SMC_SmoothMerge and SMC_LimtiDynamics, is corner smoothing still not working? Indeed. Is bDecode written from a different task (e.g. visu)? Then I would recommend to assign to a local variable (bDecodeLocal := bDecode) and use that for all FBs. Otherwise, FBs might see different values of bDecode in a single cycle, which will cause problems. It is a local variable, written from a state machine inside this program. But there is new information: During some trial and error, I tried skipping "stage 2: merge short linear segments" (SMC_SmoothMerge). And suddenly it rounds the corners, see attached image. Looking a bit closer, I noticed that (with the original program) after a download (cold start?), it in fact did round the corners, but only once. Ever next cycle in which the NC program was executed, the corners where not rounded. Not sure if there is any relation, but SMC_SmoothMerge is also the only FB which has no bAbort input. Perhaps I need to reset it (or any buffers) by other means?
Last updated: 2025-12-18
Post by youness on No source code available (cip object)
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Hi yotaro, hope your problem was resolved. I had the same, but with an other library title. This exception is not detected during compilation, but rather at a given position in the program (when switching to a given visualization). Although the exception is generated at this point, it does not involve the visualization in question. This error is due to one of 3 reasons: 1) A division by zero somewhere: The program is able to detect divisions by zero at compile time. But in the case of a variable, which takes a valid value at init and changes to 0 at a later stage. 2) An invalid pointer: (either because it has a value of 0, or because it points outside the memory reserved for the program) is being dereferenced. Locate any pointers or interfaces you have in the code and check them - you should also be wary of mixing inline modifications and pointers. 3) Array overflow: Generally when a processing operation is executed outside the array's definition range. Example: a write loop with n iterations is executed on an array of dimmension n-1. On the other hand, the error message may not appear. In the latter case, the error may have fatal consequences, as the overflow has induced writing to potentially forbidden memory areas. This problem can be explained by the fact that it's not always the adjacent memory areas of PLC_PRG that are overwritten, but the memory areas that are randomly allocated to the array during compilation. In this case, however, there is no entry in the log, so you need to integrate the "Implicit Check function", which checks the line of code generating the error. To integrate this functions, click on Application --> POU for implicit controls Regards,
Last updated: 2024-07-16
Post by john-robinson on Limiting Memory Access of an Array to Within its Bounds
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Recently we had an issue regarding some simple code to calculate a rolling average. The code indexes from zero to 199 to properly store the current input into a circular buffer which then allows us to calculate a rolling average: VAR input_5s : REAL; outs_arr : ARRAY[0..199] OF REAL; i : USINT := 0; END_VAR ___ //this code runs every five seconds, calculating a rolling average outs_arr[i] := input_5s; i := i + 1; output := OSCAT_BASIC.ARRAY_AVG(ADR(outs_arr), SIZEOF(outs_arr)); IF i >= SIZEOF(outs_arr) THEN i := 0; END_IF There is a simple bug in this code where the index will be set to 0 when it has surpassed the length of the array in bytes (800 in this case) rather than larger than the number of reals in the array (200). The solution here is simple, replacing i >= SIZEOF(outs_arr) with i >= SIZEOF(outs_arr)/SIZEOF(outs_arr[0]). In this example when the index increased to 201 and the line outs_arr[201] := input_5s was called, codesys arbitrarily wrote to the address in memory that is where outs_arr[201] would be if the array was that long. I would like to find a way to wrap the codesys array inside of a wrapper class that checks if an input is within the bounds of an array before writing to that value. I know how I would implement that for a specific array, I could create a method or class that takes an input of an array of variable length, ie. ARRAY[*] OF REAL, but I don't know how to make this for any data type. I am wondering if anyone has ever done anything similar to this, or has any better suggestions to ensure that none of the programmers on this application accidentally create code that can arbitrarily write to other locations in memory.
Last updated: 2024-03-05
Post by manuknecht on Maximum dynamic limits of MC_MoveLinearAbsolute and MC_MoveLinearRelative
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Hello all I use an axis group with two linear axes in a kinematic system. Using MC_MoveLinearAbsolute and MC_MoveLinearRelative, I am trying to realise dynamic movements (set velocity: 1 m/s, set acceleration: 30 m/s^2) with the highest possible jerk, as I want to compare this with a movement with a trapezoidal velocity profile. However, my measurements show that the axes accelerate with a maximum jerk of approx. 800 m/s^3, even if the value in the function block was set to 10,000 m/s^3. I have already increased the dynamic limits of the two axes accordingly (Velocity: 5000 u/s, Acc-/Deceleration: 250'000 u/s^2, Jerk: 100'000'000 u/s^3, where 1 u = 1 mm), but this had no effect. I have checked the input parameters of the function blocks and the VelFactor, AccFactor and JerkFactor factors are all set to the maximum (value 1). Reducing the cycle time has resulted in a higher jerk, but as we are already working with a cycle time of 1 ms, there is nothing more that can be done here. The axes themselves are still a long way from drawing the maximum current, which is why I assume that this should not be a problem either. Are there other factors or parameters that influence the dynamic limits and therefore allow faster movements? The PLC I am using is a Raspberry Pi 4 and Codesys V3.5 SP20 with all libraries up to date. Thanks in advance Manuel
Last updated: 2024-05-08
Post by rossanoparis on How to configure CODESYSControl_User.cfg in order to use a specific network card for OPCUA Server
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Thank you @eschwellinger Even tough I think the content of the link you provided is a bit messy. To bind OPCUA server to a specific adapter, I should have had insert the following section. [CmpOPCUA] NetworkAdapter=eth0 But it doesn't work, I had to insert the following section instead to get the right configuration. [CmpOPCUAServer] NetworkAdapter=eth0 Regards Rossano
Last updated: 2023-08-29
Post by nico01 on Integer with comma in visualization
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Hello everyone, I created a visualization with a lot of REAL, with one or two digits after the decimal point. This causes me problems in terms of rounding and memory... is it possible to display an integer with a comma, like with PROFACE or SIEMENS? It's just an "abuse" of display, the comma is just on the visualization. This limits the memory (16 versus 64 bytes) and rounding is easier to manage... See print screen on proface software THANKS
Last updated: 2023-09-20
Post by ofey on Symbol configuration / GVL
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Hi! I have som variables that I communicate to a Modbus Master. These variables are declared in a "Global Variable List" where I have assigned them memory addresses. To organize this mapping I want to make a MODBUS list where I show all the variable names together with the memory address. Is there an easy way to export this list from CODESYS? Either through script or some export function maybe?
Last updated: 2023-10-11
Post by ofey on Symbol configuration / GVL
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Hi! I have som variables that I communicate to a Modbus Master. These variables are declared in a "Global Variable List" where I have assigned them memory addresses. To organize this mapping I want to make a MODBUS list where I show all the variable names together with the memory address. Is there an easy way to export this list from CODESYS? Either through script or some export function maybe?
Last updated: 2023-10-11
Post by tehthoams on Find Function: Object reference not set to an instance of an object.
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Hey, Sorry this isn't super helpful, but i had this problem once and was able to resolve it. I can't recall how I solved it and whether it was a problem with my codesys installation or the project itself. If it is the codesys installation, make sure all your required libraries and plugins are installed and available. compare with a colleagues installation if possible. I vaguely recall saving a copy of my project and deleting things one by one until the error went away...
Last updated: 2023-10-30
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