Post by timvh on How to implement an interface (IElement)?
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See: https://forge.codesys.com/prj/codesys-example/element-collect/home/Home/ This contains an application "OnlineChangeSafeLinkedListExample". What you should do is create a new interface which has your "Priority" property. Then your FB should extend the base element function block and implement your own interface: E.g. FUNCTION_BLOCK MyElement EXTENDS COL.LinkedListElementBase IMPLEMENTS I_MyInterface Then the __QUERYINTERFACE does the magic to check if your "element" also implements your interface. Something like this: // Compares this element with itfElement. // Returns 0 if the elements are equal, < 0 if the element is less than itfElement, // > 0 if the element is greater than itfElement. // This method will be called from sorted collections (e.g. |COL.SortedList|) to sort the elements. // IMPORTANT: The underlying value to be compared with MUST NOT be changed during the lifecycle of the object. METHOD ElementCompareTo : INT VAR_INPUT (* The element to compare*) itfElement : COL.IElement; END_VAR VAR itfIntElement : I_MyInterface; xResult : BOOL; END_VAR // We use integer iInt1 for sorting. xResult := __QUERYINTERFACE(itfElement, itfIntElement); IF xResult THEN IF iInt1 < itfIntElement.Priority THEN ElementCompareTo := -1; ELSIF iInt1 > itfIntElement.Priority THEN ElementCompareTo := 1; ELSE ElementCompareTo := 0; END_IF ELSE ElementCompareTo := -1; END_IF
Last updated: 2024-07-22
Post by jari-koivuluoma on Problem trying Net Base Services 3.5.15.0 TCP connection
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I have a need to send messages between 2 PLCs and I cant use network variables (because of size limit) so I tried writing this simple test program. This seems to work fine. I can send messages back and forth when a first "Start server" and then "Connect client". See the attached image. However, if I disconnect the client by setting ClientConnect to false and try to re-connect then the TCP_Client just gives me TIMEOUT error. When I stop and start the server again, then Im able to reconnect. How is this supposed to work? Why reconnecting wont work. There is not other way of disconnecting the client than setting xEnable of the TCP_Client to false. This is just a testing program and I will try it on 2 seperate devices once this works. PROGRAM PLC_PRG VAR CONSTANT mySize : UDINT := 255; END_VAR VAR Server: NBS.TCP_Server; ServerIpStr: STRING := '127.0.0.1'; ServerIP: NBS.IP_ADDR; ServerPort: UINT := 50000; ServerConnection: NBS.TCP_Connection; Client: NBS.TCP_Client; ServerRead: NBS.TCP_Read; ServerWrite: NBS.TCP_Write; ServerSend: STRING(mySize); ServerReceive: STRING(mySize); ServerConnect: BOOL; bServerSend: BOOL; IP: NBS.INADDR; ConnectedClientIP: STRING; ClientPort: UINT := 50000; ClientIpStr: STRING := '192.168.1.49'; ClientIP: NBS.IP_ADDR; ClientRead: NBS.TCP_Read; ClientWrite: NBS.TCP_Write; ClientSend: STRING(mySize); ClientReceive: STRING(mySize); ClientConnect: BOOL; bClientSend: BOOL; Error: BOOL; Message: BOOL; END_VAR // Server ServerIP.sAddr := ServerIpStr; Server( ipAddr := ServerIP, uiPort := ServerPort ); ServerConnection( xEnable := Server.xEnable, hServer := Server.hServer, ); IP := ServerConnection.IPAddress; ConnectedClientIP := F_Concat7( BYTE_TO_STRING(IP.S_un_b.s_b1),'.', BYTE_TO_STRING(IP.S_un_b.s_b2),'.', BYTE_TO_STRING(IP.S_un_b.s_b3),'.', BYTE_TO_STRING(IP.S_un_b.s_b4)); ServerRead( xEnable := ServerConnection.xActive, hConnection := ServerConnection.hConnection, szSize := SIZEOF(ServerReceive), pData := ADR(ServerReceive) ); IF ServerRead.xReady AND ServerRead.szCount > 0 THEN Message := TRUE; END_IF IF ServerRead.eError > 0 THEN Error := TRUE; END_IF ServerWrite( xExecute := ServerConnection.xActive AND bServerSend, hConnection := ServerConnection.hConnection, szSize := LEN(ServerSend)+1, pData := ADR(ServerSend) ); IF ServerWrite.xDone THEN bServerSend := FALSE; END_IF IF ServerWrite.eError > 0 THEN Error := TRUE; END_IF // Client ClientIP.sAddr := ClientIpStr; Client( xEnable := ClientConnect, ipAddr := ClientIP, uiPort := ServerPort, udiTimeOut := 10000000 ); ClientRead( xEnable := Client.xActive, hConnection := Client.hConnection, szSize := SIZEOF(ClientReceive), pData := ADR(ClientReceive) ); IF ClientRead.xReady AND ClientRead.szCount > 0 THEN Message := TRUE; END_IF IF ClientRead.eError > 0 THEN Error := TRUE; END_IF ClientWrite( xExecute := Client.xActive AND bClientSend, hConnection := Client.hConnection, szSize := LEN(ClientSend)+1, pData := ADR(ClientSend) ); IF ClientWrite.xDone THEN bClientSend := FALSE; END_IF IF ClientWrite.eError > 0 THEN Error := TRUE; END_IF
Last updated: 2024-10-03
Post by ojz0r on Assignment Efficiency - Repetitive Assignment vs IF statement
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Its important that you know the difference between the two. Example 1: Coils[0] := Coils[0] OR (Buttons[0] AND Sensors[0] > 6); In this case the statements will be evaluated every scan and result in either true or false for Coils[0]. Example 2: IF NOT Coils[0] AND Buttons[0] AND (Sensors[0] > 6) THEN Coils[0] := TRUE; END_IF In this example Coils[0] will latch the result in a true evaluation, if you want it to behave the same way as example 1 then you need to do it like example 3 below: IF NOT Coils[0] AND Buttons[0] AND (Sensors[0] > 6) THEN Coils[0] := TRUE; ELSE Coils[0] := FALSE; END_IF However back to the real question. There is no problem using either example 1 or example 3, if im not requiring a latch i usually go with example 1 as it is more compact.
Last updated: 2025-03-07
Post by alexgooi on Modbus writing on value change
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Hi Duvan, You could make this in 1 single object (FB), Indeed don't use a function for this beacuse you need some memory to keep the old value. For i := 0 TO 200 BY 1 DO //Check if the value has been changed IF Old_Value[i] <> Value[i] THEN //Set the trigger to TRUE Trigger[i] := TRUE; Old_Value[i] := Value[i]; END_IF END_FOR If you define the Value array as an In_Out and the Trigger as an In_Out you arn't claiming any aditional memory to your system. You ofcourse then need to add some code arround it that does something with the trigger and writes it back to FALSE again. If you want more flexability you also could use pointers instead of using the IN_OUT FOR i := 0 TO 200 BY 1 DO address := address_Input + i * SIZEOF(*Put type here); IF Address^ <> Old_Value[i] THEN Trigger[i] := TRUE; Old_Value[i] := Address^; END_IF END_FOR
Last updated: 2024-04-02
Post by timvh on USB Game Controller with Raspberry Pi
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I'm not sure it will work, but you could try it with the CmpCharDevice library. You could create a function block that looks something like this: As input for the filename, you have to use your Linux device, e.g.: '/dev/input/event0' '/dev/input/by-path/platform-button@23-event' Off course you must also pass the pointer to the memory where the data can be written to and the size (count in number of bytes) of the buffer. FUNCTION_BLOCK FB_CharDevice VAR_INPUT szFilename: STRING; pbyBuffer : POINTER TO BYTE; udCount : UDINT; END_VAR VAR_OUTPUT iState : INT := 0; nrBytesRead : DINT; END_VAR VAR xInit : BOOL := TRUE; dFlags: DINT := CmpCharDevice.ACCESS_MODE.O_RDONLY + DINT#4000; // see details for flags: http://linux.die.net/man/2/open, + DINT#4000 is for non-blocking hDevice: CmpCharDevice.CmpCharDevice_Implementation.RTS_IEC_HANDLE := -1; Result : CmpCharDevice.CmpCharDevice_Implementation.RTS_IEC_RESULT; END_VAR IF xInit THEN hDevice := CmpCharDevice.CDOpen(szFilename, dFlags ,Result); // if it would not succeed, the result is -1 (Invalid handle) IF hDevice <> 16#FFFFFFFF AND Result = 0 THEN iState := 5; END_IF xInit := FALSE; END_IF IF iState = 5 THEN nrBytesRead := CmpCharDevice.CDRead(hDevice, pbyBuffer, udCount, Result); ELSE nrBytesRead := 0; END_IF Make sure you close the connection properly, maybe by overwriting the default FB_Exit method of the FB: // Clean up device IF hDevice <> 16#FFFFFFFF THEN __TRY CmpCharDevice.CDClose(hDevice,Result); __CATCH ; __ENDTRY iState := 0; END_IF
Last updated: 2026-05-01
Post by timvh on Specify Input Configuration "OnDialogClosed" Action to only react to certain Dialogs
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What maybe helps is the Visu Dialog ST demo project: https://store.codesys.com/en/visu-dialog-st.html This has an application IECOpenDialog where dialogs are opened using the VU.FbOpenDialogExtended function blocks. The fbOpenConfigurationDialog call has a reference (interface) to the "close listener" FB of which it's method is automatically called when the dialog is closed. This way you can create specific function blocks for each dialog when it is closed and do what you want with the data that might have been changed.
Last updated: 2023-09-28
Post by konradkmiller on Variable assignments
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I have a snippet of code that I was given as a reference in ST. ** ModbusMasterRTU( xConnect:= TRUE, IPort:= IoConfigGlobals.COM1, // IoConfigGlobals.RS232485Interface, // COM1=Front Port / Serial module = Name of module in Devices structure I/O list udiBaudrate:= 19200, usiDataBits:= 8 , eParity:= WagoTypesCom.eTTYParity.None , eStopBits:= WagoTypesCom.eTTYStopBits.One , eHandshake:= WagoTypesCom.eTTYHandshake.None , ePhysical:= WagoTypesCom.eTTYPhysicalLayer.RS485HalfDuplex, xIsConnected=> xIsConnected , xError=> , oStatus=> , eFrameType:= WagoAppPlcModbus.eMbFrameType.RTU , tTimeOut:= T#1S, utQuery:= utQuery , xTrigger:= SEND, utResponse:= utResponse)** What is the meaning of => in this context?
Last updated: 2024-07-20
Post by andrebrandt on FB string and naming
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Hi all. I have a FB written in ST. FUNCTION_BLOCK NTC10k VAR_INPUT Syst:STRING; In:REAL; END_VAR VAR_OUTPUT Out:REAL; OTag:STRING; Out_St:Struct_NTC10K; END_VAR VAR Tag:STRING; InstanceName: STRING; Structure:Struct_NTC10K; END_VAR What i'm trying to do, is to pass data to structure. In structure i want to add a tag with systemnumber and sensorname. '320.001-RT401' In pou i use this RT401: NTC10k;, and tried this RT401: NTC10k(Tag:='RT401'); Anyone done this?
Last updated: 2024-09-26
Post by warrumungi on Opening a Dialog on a specific Client from ST
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Hi Thanks, Manuel, for providing this solution and insight. I too had exactly the same problem as you did. While I did implement a custom filter, I'd also like to point out what jinlee mentioned above...I see no reference to VU.PublicVariables.Clients.Current anywhere?? In my case I only needed to show a dialog on a "master" client, not all the clients, so I filtered by IP address to do this.
Last updated: 2024-11-05
Post by sturmghost on Visualization using methods and cyclic ST-calls
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I found a way to do it: You can use, for example, the text variable property of any visualization element and call a function in it. Example: Write a test POU as a function (FUN), like MyTestFun which need a boolean Variable as an input value. Now write into the text variable property: MyTestFun(bBooleanValue) Thats it. The function is called at each visu_task cycle.
Last updated: 2024-01-22
Post by nano on Is there any support for I2C on Raspberry Pi?
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hello jdj this question can be answered well with a pretty good forge documentation: https://forge.codesys.com/drv/io-drivers/doc/Generic/ u r also able to create in codesys directly an iec-code by using the i2c-interface as driver using the codesys ide and st depending on the stepperdriver, used in yöur hat, its possible that an driver is already available in the device-repository. which mcp-device is used on the hat?
Last updated: 2024-03-01
Post by andy-yemm on Assertion Failed
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I had similar assertion failed error messages today. I am fairly new to Codesys. I tried using SFC for the first time, I usually use ST. Anyway I had errors in some of my transitions. I copied and pasted transition code and forgot to change the target of the code. I started getting lots of the assertion errors but now I have sorted out the problems and it compiles OK the assertion error messages seem to have stopped. There do not seem to be any other responses to your post, did you resolve your problem?
Last updated: 2024-03-19
Post by sahin6033 on DSE M840-001-02: DSEServiceTool transfers CodesysApp.pkg successfully, but device shows “No application loaded
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Hi, I am trying to load a test application into a DSE M840-001-02 display, but after reboot the device still shows: “No application loaded” I would like to understand whether the problem is in my project, the package creation process, or firmware/runtime compatibility. Hardware Device: DSE M840-001-02 Firmware used: M840 MKII Firmware File v4.1.2 Software CODESYS V3.5 SP12 (32-bit) DSE CODESYS Package v1.5.44 DSEServiceTool What I did Created a new empty Standard Project Selected target/template: M840-02 V4.1 Used a minimal ST program only: PROGRAM PLC_PRG VAR xAlive : BOOL := TRUE; END_VAR Confirmed: project builds PLC_PRG is assigned to MainTask created Boot Application Generated CodesysApp.pkg Put the M840 into bootloader mode Sent the package using DSEServiceTool DSEServiceTool result Transfer completes successfully and I get: connection accepted 100% download package ACK <status>OK</status> ** Example log:** Searching for controllers.... sendPackageToController: waiting for incoming data connection... sendPackageToController: connection accepted... <status>Downloading</status> <percent>20</percent> <percent>40</percent> <percent>90</percent> <percent>100</percent> sendPackageToController: sent 112cb8 bytes OK Package ...\CodesysApp.pkg transferred to controller c0a80101 OK sendPackageToController: package ACK <status>OK</status> Actual result After reboot, the display still shows: “No application loaded” Additional issue I also saw earlier At one stage I also had these fatal errors in CODESYS: [FATAL ERROR] Unresolved reference: 'IOMGRLOCKENTER' [FATAL ERROR] Unresolved reference: 'IOMGRLOCKLEAVE' I checked library versions and adjusted them to: IoDrvBase = 3.5.5.0 IoStandard = 3.5.10.0 Also, I am using CODESYS SP12, which I understand is the correct version for DSE M840. My questions If DSEServiceTool shows Status OK and package ACK, but the device still says “No application loaded”, does that mean: the .pkg was transferred but not accepted as a valid application? the package was built incorrectly? the boot application / runtime / firmware versions are still mismatched? What is the correct procedure to generate CodesysApp.pkg for M840-02 V4.1? Is there any known compatibility issue between: DSE CODESYS Package 1.5.44 M840 MKII Firmware 4.1.2 CODESYS 3.5 SP12 Has anyone successfully loaded even a minimal empty test project into M840-001-02, and if so, what exact versions/process did you use? Any help would be appreciated.
Last updated: 2026-03-17
Post by riccardo on Codesys SP19 patch 4
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Hallo everyone, I am working on new PLC of Weidmueller that uses Codesys SP19. I made the upgrade at the Patch 4 coming from patch 0. Unce made the upgrade everything is working well in the progect except the web visu user menagent. In the new version, when I perfom the login, I cannot use the keyboard of the device; the window where to digit the user name and password opens, the buttons "OK" and "Cancel" work but the system doesn't allow to put input from the device keybord, the mouse behaves as it is an image. If I active the virtual keypad or numpad it works otherwise nothing. I am wondering if it is a bug of the new package or if I must set something else. Thanks in advance, Riccardo.
Last updated: 2023-11-27
Post by orbis-tertius on 3.5 P20 hangs - no response
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Is there anybody can help me with the same problem? I have to migrate created project in ver.3.5.17.0 32BIT with runtime 4.7.0 to ver.3.5.20.0 64BIT with runtime 4.7.11.0 due to the new license. All the libraries and dependencies are updaded and there are no any errors. The first compilation and loading to the controller is being compleated well. After this being done and if I am forced to change any values or change any code in the current project, another compilation will be freezed. This problem can be solved if pressed Build/cleen or cleen all. There is another method to solve this; if project is loaded with excluded object (Alarm Configuration), repeated compilations will be done well.
Last updated: 2024-06-27
Post by andre-luis on Check if Codesys runtime is on 'Running' or 'Stopped' state?
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Hi there, I'm running the Codesys runtime on Windows 64 and I need to know if it is on "Running" or "Stopped" state just after a system crash. The following commands works perfectly well to (re)start it... net stop “CODESYS Control Win V3 - x64" net start “CODESYS Control Win V3 - x64" ...however I'm unable to determine when it is required to be call; I mean, by checking the System Tray icon, it is possible to know if it is on "Stopped" state, but I wanted to run a .BAT command to retrieve it. How can we do that?
Last updated: 2024-07-02
Post by naks on Change IP address from IEC code
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Hi, I'm working with wago 750-8212 controller. I want to change the IP address of the Ethernet adapter from webvisu. I have read some other threads in this forum and I have tried the following: Added the following text to the config file CODESYSControl.cfg: [SysSocket] Adapter.0.Name="br1" Adapter.0.EnableSetIpAndMask=1 Used the below code : IF xUpdateEthernet THEN Ethernet.Enable := FALSE; Reconfig ( xExecute := TRUE, itfNode := Ethernet, eError => ErrorReconfig, xBusy => xBusy, xDone => xDone, xError => xErrorReconfigure); IF Reconfig.xDone THEN ErrorCode := Ethernet.UpdateConfiguredIPSettings(IpAddress := NewIp, gateway := newGateway, subnetmask := newSubnetmask); END_IF IF Reconfig.xDone OR Reconfig.xError THEN reconfig(xExecute := FALSE); END_IF Ethernet.Enable := TRUE; Reconfig(xExecute := TRUE, itfNode := Ethernet ); END_IF I could change the IP address but when i restart my Controller then the IP address resets to the original, Is there anything I have missed, what else can i try ? Thank you in advance.
Last updated: 2024-07-08
Post by alez on CANopen safety , SRDO error behavior
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I have a project in which there is a Safety device in CANopen, and the PLC interfaces with it as Master. I would like to understand if it is possible to set the behavior in case one of the SRDOs that I receive from the slave is no longer received. From what I have seen, if the SRDOs are not received, the CANopen safety status becomes "Not in progress" and the mapped variables freeze at the last value detected. I want to understand if it was possible to set the variables connected to the SRDOs to take a default value (e.g. zero) in the event of a CANOpen error during reception.
Last updated: 2024-07-15
Post by trusty-squire on Strange problem with the ‘MC_SetPosition’ function
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How are the servo drives controlled? EtherCAT, step/dir pulses, other? 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. You could try to create a simplified program, with all the same parameters, that only has an MC_SetPosition FB you manually trigger and see if you are still getting the same results? 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?
Last updated: 2025-01-18
Post by trusty-squire on AXIS Rollover
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If you mean you want to shift the Origin or Zero position of your axis, you can try MC_SetPosition and set the position to 0 (if you want to take the current active position and make it the new 0. Adjust this number accordingly if/as needed). This means the servo drive keeps it's current origin position, and Codesys applies an offset to the servo drive position in the logic. You can also use the homing function of your servo drive using MC_Home and have your drive configured to set the current position as origin when it receives a homing command.
Last updated: 2025-03-11
Post by manuknecht on Using an Axis of an Axis Group in Torque Conctrol
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I don't seem to be able to use an axis, which is part of an Axis Group in torque control mode. I call the SMC_SetControllerMode FB to switch from position to torque control mode, followed by the SMC_SetTorque FB to set the desired torque. This works flawlessly for most axes, however if an axis is part of an axis group, switching the controller mode seems to work without any issues, but the desired torque is never set. SMC_SetTorque does not return an error, but fSetTorque of the axis is never changed. Disabling the axis group before does not change anything, but if I use MC_UngroupAllAxes before changing the controller mode, it all works as it should. Is there no way to control a single axis in torque control, if it is part of an axis group?
Last updated: 2025-07-17
Post by alexgooi on Codesys virtual control redundancy
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Dear Forum, I’m currently investigating the possibilities of Codesys virtual control (Linux). The research rig consists of a PC (Debian with real time kernel) with a docker server installed on it. The PC is communicating with a Remote I/O and I have to say the performance is great. The process in the container is running (soft) real time. Currently I’m checking if it is possible to replace physical controllers by remote I/O’s and run the Codesys applications on a docker server. If I’m going into this route the reliability of the server is very important (server down, complete installation down), is it possible to make the server redundant without needing 2 separate containers (including licenses), and maintaining the real time behavior? I’m not only expecting direct answers, if you have any idea or thought they are very welcome. Kind regards Alex
Last updated: 2025-09-03
Post by dkugler on Project loses 'Download time' information
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and if you copy or transfer a project to another place, copy not only the .project, copy .compileinfo .bootinfo and .bootinfo_guids then we figured out it is more often possible to go online without full download. If you build an archiv and extract it, some of this files are missing and login isn't possible without download. I work with V3.5 SP16 Patch 4. I don't know if this problem of the archiv is solved in newer Versions/SP's and I don't know what the problem of Codesys is to help out a lot of programers of this very annoying problem or at least help with a workaround
Last updated: 2025-09-18
Post by ton on How to create a stopwatch?
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One i wrote this to measure elepse time When xMeasure is true is starts en when false it stops and time is messured. FUNCTION_BLOCK FB_ElapseTime VAR_INPUT xMeasure: BOOL; END_VAR VAR_OUTPUT xRisingEdge: BOOL; xFallingEdge: BOOL; tElapsed: TIME; ltElapsed: LTIME; ltPrev_Elapsed: LTIME; ltElapsedMax: LTIME; END_VAR VAR xLastValue: BOOL; LTIMEStart: LTIME; LTIMEEnd: LTIME; tonReset: TON:= (IN:= TRUE, PT:= TIME#30S0MS); END_VAR ------------------------------------------- xRisingEdge:= (xLastValue XOR xMeasure) AND xMeasure; xFallingEdge:= (xLastValue XOR xMeasure) AND NOT xMeasure; IF xRisingEdge THEN ltPrev_Elapsed:= ltElapsed; LTIMEStart:= LTIME(); END_IF IF xMeasure OR xFallingEdge THEN LTIMEEnd:= LTIME(); END_IF ltElapsed:= LTIMEEnd - LTIMEStart; ltElapsedMax:= MAX(ltElapsedMax, ltElapsed); tElapsed:= LTIME_TO_TIME(ltElapsed); xLastValue:= xMeasure; tonReset(); IF tonReset.Q THEN tonReset.IN:= FALSE; ltElapsedMax:= LTIME#0NS; END_IF Meaby this will help.
Last updated: 2023-12-09
Post by i-campbell on What does CODESYS expect to do when I get such an error message
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you need to get the addons that the person that programmed it used. I always store an .installation-config file alongside the project. If you have lost that, then it gets a bit of a headache: I think even with SP18 you can hit yes to open it anyway, and it will suggest which addons it thinks are missing, if you double click the yellow "missing-addons" in the status bar. If you know you have the right addons, you can do a "Save As.." and it will write your current addon list to the file, and you wont get the error next time.
Last updated: 2024-01-08
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