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

Post by clarenced on Multiple applications on one device sharing variables. ^{CODESYS Forge talk (Post)}
I got this working using OPC UA. In the logic application I just added a Symbol Configuration. In the HMI application I added a Data Sources Manager and OPC UA Data Source. The one thing I don't like is the way the tags end up being named in the HMI application. In the logic application I have a program named PLC_PRG. It has a variable named testDINT. In the logic application the name I get for this variable is DeviceSet.CODESYS_Control_Win_V3_x64.Resources.Logic.Programs.PLC_PRG.testDINT. This is very long and looks like it could change if I used this on a different device type. Any ideas how I could get this name shortened down to just PLC_PRG.testDINT like it is on the Logic application?
Last updated: 2025-03-06

Post by clarenced on Multiple applications on one device sharing variables. ^{CODESYS Forge talk (Post)}
I got this working using OPC UA. In the logic application I just added a Symbol Configuration. In the HMI application I added a Data Sources Manager and OPC UA Data Source. The one thing I don't like is the way the tags end up being named in the HMI application. In the logic application I have a program named PLC_PRG. It has a variable named testDINT. In the HMI application the name I get for this variable is DeviceSet.CODESYS_Control_Win_V3_x64.Resources.Logic.Programs.PLC_PRG.testDINT. This is very long and looks like it could change if I used this on a different device type. Any ideas how I could get this name shortened down to just PLC_PRG.testDINT like it is on the Logic application?
Last updated: 2025-03-06

Post by simotion on Inheritance of axis ^{CODESYS Forge talk (Post)}
I have developped a function block 'Axis' the inherits from 'AXIS_REF_SM3' -> FUNCTION_BLOCK Axis EXTENDS AXIS_REF_SM3 In my global variable list I define a variable MasterDrive of type Axis and assign Axis1. Axis1 is a virtual drive (AXIS_REF_VIRTUAL_SM3). This type should inherit from AXIS_REF_VIRTUAL. VAR_GLOBAL MasterDrive : Axis := Axis1; However I get the error 'Cannot convert type'. What is the way to obtain what I want : function block inheriting AXIS_REF_SM3 and initialising this function block with a Softmotion virtual or real axis?
Last updated: 2023-12-07

Post by timvh on Device logon problem following fresh install ^{CODESYS Forge talk (Post)}
In your project you selected the "CODESYS Control Win V3" as device, but the device you want to connect to is a "CODESYS Control Win V3 x64". Those are not the same. If you double click on the device during the network scan, you will get information that these are not the same, but that you can change the type in your project to the x64 bit type. Another option is to "right-click" on the device in the device tree of your project and select "update device" then select the x64 type.
Last updated: 2024-03-19

Post by mikek10 on Error IoDrvEthernetIP: Connection Failure. (16#1) How to solve ^{CODESYS Forge talk (Post)}
Your connection configuration should look something like the attachment. Consuming assembly O->T will be the hex of the assembly you want to reference for output data - I want 102 (DO Data Only) shown in the Wago web page 102 = 16#66. Producing assembly (T->O) is the assembly you require for input data - again shown in the Wago web page - I want 108 (DI Data Only) or 16#6C Then set the number of bytes as per the data in the Wago web page too (both 2 in my case)
Last updated: 2024-07-22

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 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: 5 days ago

Post by nehaltrivedi96 on Modbus connection via Qronox PCD3 M6893 ^{CODESYS Forge talk (Post)}
Hello, I am currently scaling 4-20mA signals and the scaled output (temperature) has to be sent via modbus protocol to a tool like doctor modbus or modbus poll. I have defined my inputs as real as and the output is also real, but to send this output via modbus it has to be of word. So how will i convert real into word and then send the generated output via modbus?
Last updated: 2026-02-18

Post by manuknecht on Persistence Manager does not save alphabetically first value ^{CODESYS Forge talk (Post)}
After some more digging I realized that I get an error on the PLC Logger saying PersistenceChannel: 150 (invalid type in data: SimpleLibrary). I suppose the issue could be found in the ConfigData, which is automatically generated and which looks like this: 1 9##83 SimpleLibrary#GVL.aMoreZeros.[1]#0#64512#15#0 <[2]#0#64520#15#0 <[3]#0#64528#15#0 <[4]#0#64536#15#0 <#0#64544#15#0 <[6]#0#64552#15#0 <<lrVar#0#64560#15#0 <strVar#0#64428#16#80 <uiDummy#0#64370#11#0 Perhaps the fact that the variable is stored within a library confused the compiler? I tried changing the PersistenceChannel parameters to xCompressTags := FALSE which changed the entry in the data file from _xCompressTags BOOL:TRUE _xCompressTags BOOL:FALSE but the actual content of the data file and also the config data did not change.
Last updated: 2023-10-17

Post by paulorb on STRUCT AT %MW1000 ^{CODESYS Forge talk (Post)}
Hi I am trying to use STRUCT to parse commands from Modbus/TCP, Modbus client will fill the bytes related to a specific command (type, parameters), then PLC (Codesys) will access the command parameters. A STRUCT will simplify a lot the process of parsing the data, so I don't need to parse byte per byte, address will be mapped to a struct and I can use it for parsing the data. From what I understood, the compiler does not allow me to specify the location of the struct for a %MW register. VAR_COMMAND AT %MW1002: structGenericModbusCommand; This will throw: Bad declaration, use '%ML' for 'structGenericModbusCommand' variable But If I change it to %ML, when you go online you see that it is actually allocating the struct in another memory address. When we go online, on GVL we can see: VAR_COMMAND. structGenericModbusCommand %ML1002 commandType COMMANDTYPE %MB8016 ... %MB8020 I am not specifying a pointer or a reference it is a struct type, why is it mapping to a %MW location (random one). How can I control where it is mapping to? I need a consistent way to map STRUCT to specific modbus address. Is it possible? Thanks, Paulo Note I am using a Codesys OEM: Schneider Machine Expert Logic Builder (M241)
Last updated: 2024-08-13

Post by ph0010421 on How to manage variable types larger than 64 bits - Ethernet/IP ^{CODESYS Forge talk (Post)}
My guess is that's a STRING, not an INT type. And it's 128 bytes, not bits
Last updated: 2024-09-23

Post by athuum on Error 'Library not found' and 'Unkown type' ^{CODESYS Forge talk (Post)}
I have found the solution, the CmpEventMgr version has to correspond with the 3sLicense version.
Last updated: 2024-10-10

Post by eschwellinger on Server not adding PLC ^{CODESYS Forge talk (Post)}
which plc type do you try to add? Unique serial numbers of the plc are mandatory too.
Last updated: 2025-02-17

Post by timvh on Inheritence of struct, ^{CODESYS Forge talk (Post)}
Maybe the ANY type can help? https://content.helpme-codesys.com/en/CODESYS%20Development%20System/_cds_datatype_any.html
Last updated: 2025-03-08

Post by jampid on How do I fix ";Internal Error (x86-64): Invalid type size" error? ^{CODESYS Forge talk (Post)}
Bonjour Mucleus, peut-être mettre à jour le Device et recompiler?
Last updated: 2025-04-16

Post by simotion on Property ^{CODESYS Forge talk (Post)}
Why can't a property be of type REFERENCE TO? Plc goes to stop if I try that.
Last updated: 2023-12-14

Post by hyplcmotion on The element of type 'VisuFbElemImage' could not be updated. Reason: Index was outside the bounds of the array. ^{CODESYS Forge talk (Post)}
Hello, I’m encountering the same issue. I only receive these errors when downloading to the PLC—there are no errors during the build—after upgrading to CODESYS 3.5.21.10. Is there any known fix or recommended solution? Visualization seems running ok, no PLC log error. Visualization: Error: The element of type 'VisuFbLabel' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemSimple' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemSimple' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemImage' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemSimple' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemSimple' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemImage' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemButton' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemButton' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds. Visualization: Error: The element of type 'VisuFbElemSimple' could not be updated. Reason: Source array was not long enough. Check srcIndex and length, and the array's lower bounds.
Last updated: 2026-01-26

Post by hammer on Cartesian XY Chart — 2-D array binding: "Element to use" enumerates the wrong dimension ^{CODESYS Forge talk (Post)}
Title: Cartesian XY Chart — 2-D array binding: "Element to use" enumerates the wrong dimension; documented example (Dialog: XY Chart Configuration, "Two-dimensional array of base type REAL") appears transposed Product / version: CODESYS Development System V3.5 SP21 Patch 40 (3.5.21.40). Cartesian XY Chart visualization element (System_VisuElemXYChart / VisuElemXYChart). Summary: When a curve's Data X/Data Y is bound to a two-dimensional array, the element treats the last array dimension as the per-point record (the one selected by "Element to use") and iterates the first dimension as the sequence of curve points. The online documentation's worked example has the dimensions in the opposite order, so following it produces a non-functional curve and a nonsensical "Element to use" list. Steps to reproduce (fails — matches the documented layout): 1. Declare aData : ARRAY[0..1, 0..4095] OF LREAL; (2 data sets × 4096 points, i.e. first dimension = set, second = point). 2. In XY Chart Configuration, bind a curve's Data X (and Y) Variable to this array. 3. Observe the "Element to use" combobox. Actual result: The "Element to use" combobox lists 4096 entries (the indices of the second dimension) instead of 2 (the data sets in the first dimension). Selecting a row does not produce the expected curve; at most a single/degenerate point is plotted. Steps to reproduce (works — transposed): 1. Declare aData : ARRAY[0..4095, 0..1] OF LREAL; (points first, set second). 2. Bind Data X/Y to this array; "Element to use" now correctly lists [0] and [1]. 3. Populate aData[point, set] and the curve plots as expected. Expected result: Either the documented example should select the data set from the first dimension (as its [1]/[2] "Element to use" implies), or the documentation should state that the last dimension is the record dimension (stride) and the first dimension is the point sequence — consistent with how the element actually behaves. Analysis: The behavior is self-consistent if the element always walks a single array by a fixed byte stride, reading one element per point — the same mechanism as the documented "one-dimensional array of a DUT" case, where it strides by SIZEOF(DUT) and "Element to use" picks the member offset. For a 2-D array the record is the last dimension: to plot column/set c it starts at [0, c] and strides by the last-dimension length to reach [1, c], [2, c], … (row-major layout makes this a contiguous column walk). Under that rule, ARRAY[0..N, 0..1] is correct (record length 2 → "Element to use" [0]/[1]), and the documented ARRAY[1..2, 1..50] with "Element to use" [1]/[2] is transposed. Documentation reference: Dialog: XY Chart Configuration → Data X / Data Y → "Example: Two-dimensional array of the base type REAL" (ARRAY[1..2, 1..50], Element to use [1]/[2], "100 array values are displayed"). This example does not plot as described in 3.5.21.40; transposing to ARRAY[1..50, 1..2] does. Request: Please confirm whether this is (a) a documentation error (example dimensions reversed) or (b) an element defect (combobox enumerates the wrong dimension). Either way, a corrected example plus an explicit statement of which dimension is the point sequence vs. the record/stride dimension would prevent others from hitting this. Two separate 1-D arrays for Data X and Data Y work correctly and are unaffected.
Last updated: 2026-08-14

Post by timvh on FB string and naming ^{CODESYS Forge talk (Post)}
Really not clear what you are trying to do, but isn't a Struct enough? So add an object of the type DUT to the Application. Then create a structure TYPE ST_Sensor : STRUCT sName : STRING; uiNumber : UINT; END_STRUCT END_TYPE Then in you application add an instance of this Structure stSensor1 : ST_Sensor := (sName := 'my sensor', uiNumber := 1); or use it like this stSensor1.sName := 'my sensor';
Last updated: 2024-09-28

Post by eschwellinger on Scan Network on gateway created with Control Sl ^{CODESYS Forge talk (Post)}
it seems that the device you scan, is not the same type which you have added to the project in CODESYS. Virtual Control is Arm 64 SL so please select this type in CODESYS when you generate a new Application..or right click to the device- update device - virtual Control Arm 64 SL
Last updated: 2024-10-16

Post by rafaelbrito on The element of type 'VisuFbElemImage' could not be updated. Reason: Index was outside the bounds of the array. ^{CODESYS Forge talk (Post)}
When trying to use the Visualization ToolBox, no objects appear and the following error appears. Could you tell me what this error could be? The element of type 'VisuFbElemImage' could not be updated. Reason: Index was outside the bounds of the array. Can anyone tell me what this error is?
Last updated: 2024-12-03

Post by benemenn on Type mappings in Datasource ^{CODESYS Forge talk (Post)}
Hi! I am trying to achieve the same issue. Has there been a solution? I can create the mapping, and map the local variable, but somehow the object does not update. Furthermore, i have an issue where codesys doesn't let me set ReadWrite accesses to the variables in the "Type Mapping" place. The access will simply not be set. Has anyone ran int that issue?
Last updated: 2025-04-02

Post by mucleus on How do I fix ";Internal Error (x86-64): Invalid type size" error? ^{CODESYS Forge talk (Post)}
I opened the project file of version 3.5.19.7 in 3.5.21.0. I updated all the environment of the project to the latest and compiled it. When I compile it, I get an error ";Internal Error (x86-64): Invalid type size". How can I fix this error? I will wait for your help.
Last updated: 2025-04-15

Post by zoppp on Visu Frame-configuration___text will not work ^{CODESYS Forge talk (Post)}
Yup, I've been having the exact same issue. A workaround that was working until Visu 4.8.0.0 was using TextList as the type in the frame configuration and then wrapping the text in quotes when configuring it. Im not sure if it will work with variables and I know it does not work if the type is text.
Last updated: 2025-06-17

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