Post by timvh on USB Game Controller with Raspberry Pi ^{CODESYS Forge talk (Post)}
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 darwin03 on Mismatch between coordinate monitor and actual motion using SMC_GroupJog2, MC_MoveLinearAbsolute (6DOF) ^{CODESYS Forge talk (Post)}
Hi Georg, Thank you very much for your help and for taking the time to look into my issue! After reversing the directions of A2 and A3, the robot now moves correctly according to the coordinate system. That solved the main issue with the joint rotation directions. However, I still have two issues: When I command the robot to move along the X, Y, and Z axes, the movement seems slightly off, and the trajectory appears somewhat diagonal instead of following a straight line along the commanded axis. The A6 axis also rotates during the movement, whereas I would expect it to maintain its orientation and remain unchanged. Do you have any suggestions on how I could correct the Cartesian linear movement and keep A6 fixed during the motion? Thank you again for your support! Best regards, Darwin Video link: https://drive.google.com/file/d/1tnokDYoNUEDy--eQtX_JZavMVSn-a9Le/view?usp=sharing
Last updated: 2026-10-15

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

Post by ryandmg on Web Client (HMI) Disconnects from Webvisu (Weidmuller u-OS) ^{CODESYS Forge talk (Post)}
Hey Everyone, I'm having a bit of a struggle finding settings that will reliably maintain a connection between the webvisu and a touchscreen client. Every so often the HMI disconnects and will perpetually display the red spinning arrow with the "Error Happened, Will resume automatically" text. Power cycling the HMI to force a reconnect will re-establish comms. It seems to happen during periods of inactivity if that's a clue. From what I've gathered so far this seems to have something to do with the webvisu update rate, buffer size as well as the visu task scan rate. We first tried the default settings as follows: Webvisu Update Rate: 200 ms Webvisu Buffer Size: 50,000 Visu Task Scan Rate: 100 ms Priority 31 Other Tasks for Reference: Main Task Scan Rate: 100 ms Priority 1 Alarm Manager Scan Rate: 50 ms Priority 31 Ethercat Task: 4 ms Priority 1 This would disconnect some what regularly. We then made the following changes to try and stabilize: Webvisu Update Rate: 150 ms Webvisu Buffer Size: 75,000 Visu Task Scan Rate: 75 ms Kept other tasks the same. This seems to disconnect even more frequently. Also for reference the network is very small and only consists of the PLC, a small switch and the HMI. We're also not controlling frames from outside the visu program itself. The frame changes are all done natively. Any suggestions to get this to stop disconnecting? Oh and whatever the issue is the log does not record it. Figured I would ask here before opening a ticket. Thanks in advance for your help!
Last updated: 2023-09-06

Post by manuknecht on Opening a Dialog on a specific Client from ST ^{CODESYS Forge talk (Post)}
I managed to find a solution that seems to work reliably. As the VU.Globals.CurrentClient-filter accesses the CURRENTCLIENTID or at least a similar, internal variable it can only be used if called from a certain client (e.g. from a button in a visualization). My solution works by implementing a new client filter that compares the client ID of all clients to the ID of the last client that was used. The variable containing the data of the last client is defined as: G_LastClient : VU.IVisualizationClient; // Copy of last client that detected click This last client is then updated every time a button is pressed using the Execute ST-Code input configuration of the button: G_LastClient := VU.PublicVariables.Clients.Current; Next, I created a function block that implements the client filter interface as so: FUNCTION_BLOCK FB_LastClientFilter IMPLEMENTS VU.IVisualizationClientFilter VAR_INPUT END_VAR VAR_OUTPUT END_VAR VAR END_VAR Then i added a method to the FB called IsAccepted which is used to filter out the client. When creating the method, it should automatically be filled with the according variable declaration, as it is defined in the interface: (* For every client can be desided, if it is accepted. ``TRUE``: Client is accepted*) METHOD IsAccepted : BOOL VAR_INPUT (* The client, to check*) itfClient : VU.IVisualizationClient; END_VAR Now the client can be compared to the last used client as such: // check if clientID corresponds to clientID of last recorderd client IF itfCLient.ClientId = G_LastClient.ClientId THEN IsAccepted := TRUE; ELSE IsAccepted := FALSE; END_IF To make use of this custom client filter, initialize a variable with the client filter: LastClient : FB_LastClientFilter; // Client filter to find last used client Then use this client filter when opening or closing a dialog from ST: fbOpenMyDialog(itfClientFilter:=LastClient,xExecute:=TRUE,sDialogName:='VIS_MyDialog_DLG');
Last updated: 2023-09-27

Post by mubeta on Some 'pathetic' errors in SoftMotion program ^{CODESYS Forge talk (Post)}
Yes, this is the error the sometimes show up. What make me crazy is the fact that it happens randomly and not each times. I know very well where the problem is, in wich one program row it's located. For each actions of the state machine I have all events recorded with log on text file. it is not problematic for me to find the application point of the fault, but I need to understand why occasionally and for no apparent reason, switching the state machine and thus changing the motion FB, sends the axis into failure (but only occasionally). For example, one case that is often problematic is the execution of the Axis Halt instruction. When, after a MoveAbosulte instruction this returns the event as 'done' and indeed the axis is in standstill, the state machine first sets the move instruction to FALSE, and the next cycle sets the Halt request to TRUE. Some of the time everything works out fine. Occasionally, however, in this exchange, the axis goes into fault, also losing the OPERATIONAL state. Meanwhile, I would like to understand why the motion FB instances must still be called even after the Execute is set to FALSE, especially in view of the fact that the next instruction is programmed to abort the previous one, with BufferMode set to 'Aborting'. All these unnecessary FB calls are an unnecessary overhead on the CPU anyway. Is there any precise rule about when to cease calling the various instances? (It should precisely be the 'done' status that says this one has finished its work).
Last updated: 2024-07-18

Post by tk096 on Some 'pathetic' errors in SoftMotion program ^{CODESYS Forge talk (Post)}
Meanwhile, I would like to understand why the motion FB instances must still be called even after the Execute is set to FALSE, especially in view of the fact that the next instruction is programmed to abort the previous one, with BufferMode set to 'Aborting'. All these unnecessary FB calls are an unnecessary overhead on the CPU anyway. Is there any precise rule about when to cease calling the various instances? (It should precisely be the 'done' status that says this one has finished its work). In general: - Motion function blocks have to be called until they report 'Done', 'Error', 'CommandAborted' or a subsequent motion FB with BufferMode=Aborting is started in the current cycle. - Setting the Execute input to FALSE will not abort any ongoing motion of the motion function block. For example, one case that is often problematic is the execution of the Axis Halt instruction. When, after a MoveAbosulte instruction this returns the event as 'done' and indeed the axis is in standstill, the state machine first sets the move instruction to FALSE, and the next cycle sets the Halt request to TRUE. Some of the time everything works out fine. Occasionally, however, in this exchange, the axis goes into fault, also losing the OPERATIONAL state. I think the error SMC_FB_WASNT_CALLED_DURING_MOTION is only a follow-up (and misleading) error that results from the axis not being in operational state anymore (bus problems). Is there an error 'regulator or start not set' in the device log before the error 'motion generating FB wasn't called for at least one cycle'? Which error does the respective function block (Halt.ErrorId) report?
Last updated: 2024-07-22

Post by mubeta on Some 'pathetic' errors in SoftMotion program ^{CODESYS Forge talk (Post)}
Thank you for your interest. Your answers are in line with what I knew, so at least it comforts me that I did not misinterpret the situation. However, I don't have an exact match as, for this project over the past few days I have: 1) I have gone back to leaving the various FBs of the motion always called, all of them, and in the state machine I use a boolean to activate the various useful Execute. (But in the future I want to go back and try the programming technique with which I wanted to develop this project); 2) For the occasional error: SMC_FB_WASNT_CALLED_DURING_MOTION perhaps it was due to the fact that I had set the Ethercat bus synchronism only at the CAN master level, but not at the level of individual drives. I have now also activated it for the individual drives and it does indeed seem to have been resolved, but having also adopted the programming technique mentioned in point 1), I cannot say whether this was the solution to the problem, or instead the previous point. Is there an error ‘regulator or start not set’ in the device log before the error ‘motion generating FB wasn't called for at least one cycle’? I can't answer that right now. By now the machine is running and I am no longer there, at this one. Also, I seem to remember that the 'fbeFBerror' drive structure (5-element array), does not cycle, BUT ONCE THE 5 EVENTS AFTER SWITCHING ON, IT DOES NOT UPDATE ANYMORE (but that's another issue), so diagnostics were not easy.
Last updated: 2024-07-24

Post by gorditron on I2C Communication with ^{CODESYS Forge talk (Post)}
Hello, I have problems with the I2C communication to an ADS7828 AD converter. I don't get any value back from the chip. I use a Kontron chip (ARM 32SC) with Linux as the operating system. I also use the CmpCharDevice library. ADS7828 parameters Address: A1 = 0 / A0 = 0 = SD = 1 = Single End C2 = 0 / C1= 0 / C0= 0 / Channel 0 PD1 = Internal Reference and PD0 = AD Converter ON Here is my code: VAR b_i2cAdr : BYTE := 16#48; (* Standard I2C-Adresse des ADS7828 *) x_Init: BOOL;(* Flag für die Initialisierung *) b_config_byte: BYTE;(* Konfigurationsbyte für den ADS7828 *) ab_cmd_buffer : ARRAY [0..0] OF BYTE; (* Buffer für den Befehl *) ab_data_buffer : ARRAY [0..1] OF BYTE; (* Buffer für die empfangenen Daten *) ui_adc_value_1 : UINT; (* Ausgelesener ADC-Wert *) I2C_Handle: RTS_IEC_HANDLE; (* Handle für das I2C-Device *) di_result_open: DINT;(* Ergebnis der Funktionsaufrufe *) di_result_adr: DINT;(* Ergebnis der Funktionsaufrufe *) di_result_wr_cmd: DINT;(* Ergebnis der Funktionsaufrufe *) di_result_rd_cmd: DINT;(* Ergebnis der Funktionsaufrufe *) di_result_close: DINT;(* Ergebnis der Funktionsaufrufe *) END_VAR //*** Init from the I2C communication port *** IF NOT x_Init THEN I2C_Handle := CDOpen(szFile:= '/dev/i2c-0', dFlags:= O_RDWR, pResult:= ADR(di_result_open)); //* I2C opening * //*** set of the I2C address *** CDIoctl(hFile:=I2C_Handle , dRequest:=1795 , dParameter:=b_i2cAdr , pResult:=ADR(di_result_adr) ); x_Init := TRUE; END_IF (* Hauptlogik *) IF I2C_Handle <> 0 THEN (* Konfigurationsbyte setzen: Single-Ended Kanal 0, interne Referenz *) b_config_byte := 16#8C; (* 10001100b: AIN0, interne Referenz, Single-Ended *) ab_cmd_buffer[0] := b_config_byte; (* Schreiboperation zum Konfigurieren des Chips *) CDWrite(hFile:= I2C_Handle, pbyBuffer:= ADR(ab_cmd_buffer), udCount:= SIZEOF(ab_cmd_buffer), pResult:= ADR(di_result_wr_cmd)); IF di_result_wr_cmd = 0 THEN (* Leseoperation, um den ADC-Wert zu erhalten *) CDRead(hFile:= I2C_Handle, pbyBuffer:= ADR(ab_data_buffer), udCount:= SIZEOF(ab_data_buffer), pResult:= ADR(di_result_rd_cmd)); IF di_result_rd_cmd = 0 THEN (* ADC-Wert aus den Daten extrahieren *) ui_adc_value_1 := SHL(TO_UINT(ab_data_buffer[0]), 8) OR TO_UINT(ab_data_buffer[1]); ELSE (* Fehler beim Lesen der Daten *) ui_adc_value_1 := 0; (* ADC-Wert auf 0 setzen *) END_IF ELSE (* Fehler beim Schreiben der Konfiguration *) ui_adc_value_1 := 0; END_IF END_IF
Last updated: 2024-12-13

Post by timo on String nach erlaubten/unerlaubten Zeichen durchsuchen ^{CODESYS Forge talk (Post)}
Hallo, Ich bastele gerade an einer möglichst einfachen Möglichkeit mit der ich prüfen kann ob ein String Sonderzeichen enthält. Mein Ansatz ist ein ST FB mit einer Case Schrittkette. Ich vergleiche jedes Zeichen des Strings mit allen Zeichen eines vorher definierten Strings erlaubter Zeichen, der A-Z, a-z und 0-9 enthält und ggf angepasst werden kann, wenn ich weitere Zeichen erlaube. Leider wird meine j Zählervariable nicht richtig ausgeführt. Hat da jemand eine Idee? Oder gibt es eine einfachere Lösung/einen fertigen FB den ich mir anschauen kann? FUNCTION_BLOCK Sonderzeichen_Check VAR_INPUT inputString : STRING; // Zu prüfender String startCheck : BOOL; // Startsignal END_VAR VAR_OUTPUT ok : BOOL; // TRUE, wenn keine ungültigen Zeichen END_VAR VAR i : INT := 1; // Input-String Zähler j : INT := 1; // erlaubte Zeichen Zähler allowedChars: STRING := 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'; // Erlaubte Zeichen currentChar : STRING[1]; // Aktuelles Zeichen step : INT := 0; // Schritt END_VAR CASE step OF 0: // Warten auf Start IF startCheck THEN step := 10; END_IF 10: // Initialisierungen i := 1; j := 1; ok := TRUE; // Standard: ok step := 20; 20: // Durchgehen des Eingangs-Strings IF i <= LEN(inputString) THEN currentChar := MID(inputString, i, 1); // Aktuelles Zeichen step := 30; ELSE step := 70; // Alle Zeichen ok END_IF 30: // Durchgehen der erlaubten Zeichen IF j <= LEN(allowedChars) THEN step := 40; // Zu Schritt 40 ELSE step := 60; // Ungültiges Zeichen END_IF 40: // Vergleich IF currentChar = MID(allowedChars, j, 1) THEN i := i + 1; // Nächstes Zeichen im Input step := 20; ELSE j := j + 1; // Nächstes erlaubtes Zeichen step := 30; END_IF 60: // Ungültiges Zeichen ok := FALSE; // Setze auf FALSE step := 0; 70: // Alle Zeichen ok step := 0; END_CASE
Last updated: 2025-01-20

Post by clarenced on Multiple applications on one device sharing variables. ^{CODESYS Forge talk (Post)}
I am looking for an example of how to run 2 applications on 1 device that would have global variables shared between the two apps. In this case what I am trying to do is to have the main program logic run as one application and then have the visualization run as a second application. I find this https://us.store.codesys.com/media/n98_media_assets/files/000013-F/0/Multiple%20Applications_en.pdf, that talks about exactly what I want to do, but I can't find the download. The main reason I want to do this is for download speed. Right now it takes at least a minute to download our application to the PLC. A simple program downloads to the PLC in a very short time, but add visualization and the download time gets much longer. If I could download the program separately from the visualization I think that a simple program change would take very little time to download. I have tried create a GVL in the POUs view. This partly works in that both applications can see the GVL, but they each create their own instance of it and the variables are not shared between the two apps. There are ideas of using OPCUA but this raises problems with licensing and having to move any variable that needs to be shared into the Symbol Configuration. This adds a lot of management to keep this up to date. Any ideas would be appreciated thanks.
Last updated: 2025-02-20

Post by serwis on Dynamic target position tracking ^{CODESYS Forge talk (Post)}
Hello, I am trying to control a servo drive and dynamically set its position. I control the drive via EtherCAT with a cycle time of 500us. I use the MC_MoveAbsolute block for this. The problem is that when using a PID controller, I generate the positions I want the drive to move to on an ongoing basis, and I would like the position to be set immediately. The MC_MoveAbsolute block must receive a rising edge to execute, and I would like the movement to be performed without waiting for this edge. I have created a function that generates a rising edge every 1 ms, but I am unable to change this time to 500 µs because the TON function does not support times shorter than 1 ms. Below is the code to call the rising edge: IF Exe = TRUE THEN delay1(IN:=TRUE, PT:=T#1MS); IF delay1.Q = TRUE THEN Exe := FALSE; delay1(IN:=FALSE); END_IF END_IF IF Exe = FALSE THEN delay(IN:=TRUE, PT:=T#1MS); IF delay.Q = TRUE THEN Exe := TRUE; delay(IN:=FALSE); END_IF END_IF END_IF Here is the code for calling the MC_MoveAbsolute function: MoveDegree( Axis:= Tilt, Execute:= Exe, Position:= position_target - (base_angle_real * feedforward_turn), Velocity:= vel, Acceleration:= acc, Deceleration:= dec, Jerk:= jerk, Direction:= MC_DIRECTION.shortest, BufferMode:= MC_BUFFER_MODE.Aborting, Done=> , Busy=> , Active=> , CommandAborted=> , Error=> , ErrorID=> ); I realize that there are probably better methods for performing this type of task. How can I implement motion with a dynamically changing setpoint? THANKS
Last updated: 2025-09-05

Post by imdatatas on The default ramp type selection in SoftMotion V4.18.0.0 is Quadratic ^{CODESYS Forge talk (Post)}
Dear @gseidel, Thank you for your clarification. I fully agree that the quadratic ramp type may have certain technical advantages. However, the main problem is backward compatibility and consistency across projects. In many automation projects, application developers rely on the fact that creating a new axis object will behave exactly the same way as in previous versions. With SoftMotion V4.18.0.0 and later, if an application developer adds an axis and overlooks the changed default, the motion function blocks behave differently than expected. In particular, since the Jerk value in SM3_Basic function blocks is ineffective in trapezoid ramp type, users are accustomed to leaving this parameter empty in their projects. In many existing projects, this variable has not even been assigned. When the default is changed to quadratic, the Jerk parameter suddenly becomes relevant, which can cause errors or unexpected behaviour in the field. From a user perspective, a default setting should always be the “safe” and “expected” option, while alternative options (like quadratic) can be selected manually if desired. Keeping the default as trapezoid ensures compatibility with existing projects and prevents unexpected issues, while still allowing users to benefit from quadratic ramps if they explicitly choose so. For these reasons, I kindly ask you to reconsider making trapezoid the default again. This would significantly reduce the risk of unexpected behaviour in future projects while still preserving the advantages of the quadratic ramp type for those who actively select it. Of course, the final decision is entirely at your discretion. Best Regards, imdatatas
Last updated: 2025-09-26

Post by matteodigani on Error using function block "Write alias address" ^{CODESYS Forge talk (Post)}
Hi, I've got a problem using the function block "Write alias address" (ETCStack library 4.9.0.0). this is the code: EtherCAT_1(); IF EtherCAT_1.ConfigRead AND enable THEN CASE seq OF 0: exec := FALSE; T.IN := TRUE; T.PT := T#10S; T(); IF T.Q THEN seq := 1; T.IN := FALSE; END_IF ; 1: T.IN := FALSE; T(); //THIS ONE WORK CORRECTLY! WrAliasAdd.xAbort := FALSE; WrAliasAdd.usiCom := DWORD_TO_USINT(EtherCAT_1.InstanceNumber); WrAliasAdd.wSlaveAddress := 1002; WrAliasAdd.xAutoIncAdr := FALSE; WrAliasAdd.uiAliasAddress := 19; WrAliasAdd.udiTimeOut := 3000; IF start THEN exec := TRUE; ELSE IF NOT error THEN start := TRUE; END_IF END_IF IF WrAliasAdd.xDone THEN start := FALSE; done := TRUE; error := FALSE; exec := FALSE; seq := 5; END_IF IF WrAliasAdd.xError THEN start := FALSE; done := FALSE; error := TRUE; exec := FALSE; END_IF ; 5: exec := FALSE; T.IN := TRUE; T.PT := T#1S; T(); IF T.Q THEN seq := 10; END_IF ; 10: T.IN := FALSE; T(); //THIS ONE GIVES ME AN ERROR! WrAliasAdd.xAbort := FALSE; WrAliasAdd.usiCom := DWORD_TO_USINT(EtherCAT_1.InstanceNumber); WrAliasAdd.wSlaveAddress := 1006; WrAliasAdd.xAutoIncAdr := FALSE; WrAliasAdd.uiAliasAddress := 25; WrAliasAdd.udiTimeOut := 1000; IF start THEN exec := TRUE; ELSE IF NOT error THEN start := TRUE; END_IF END_IF IF WrAliasAdd.xDone THEN start := FALSE; done := TRUE; error := FALSE; exec := FALSE; seq := 99; END_IF IF WrAliasAdd.xError THEN start := FALSE; done := FALSE; error := TRUE; exec := FALSE; END_IF ; ELSE ; END_CASE WrAliasAdd(xExecute := exec); END_IF The first one slave ethercat works correctly, but the other one gives me an error. Attached the ethercat configuration of the devices. All the devices are set "Optional". So my idea is to enable only the first one (1002) and the fifth one (1006).
Last updated: 2025-10-01

Post by mondinmr on Why SysPipeWindows is not implemented in RTE? ^{CODESYS Forge talk (Post)}
This library would be very useful for IPC communications. Using a UDP socket on localhost is unpredictable, as with slightly loaded machines it does not even guarantee packet delivery locally. Using TCP creates a lot of overhead. Message named pipes would be an excellent solution for Windows RTE. On Linux, since the release of the extension package, there is no issue, as it is sufficient to develop a component. However, although now 90% of our clients understand that Linux runtimes are better in every way compared to Windows RTE, especially from the security aspect (Not in kernel space) and the issues with Windows updates, 10% stubbornly insist (sometimes for trivial commercial reasons) on using Windows. Managing IPC with circular buffers in shared memory is quite ugly, or rather really ugly and unaesthetic. In the manuals, I saw the SysPipeWindows libraries, so I decided to test them, but unfortunately, I noticed that they are not implemented for RTE devices. Technically, I could try to open them as regular files, but SysFileOpen returns 16#27 or 16#39 depending on how I set the name (direction of the slashes). Here is the code to create shared memory and named pipes. Shared memory work great, named pipes no! #ifdef Q_OS_WIN32 SECURITY_ATTRIBUTES sa; SECURITY_DESCRIPTOR sd; InitializeSecurityDescriptor(&sd, SECURITY_DESCRIPTOR_REVISION); SetSecurityDescriptorDacl(&sd, TRUE, NULL, FALSE); sa.nLength = sizeof(SECURITY_ATTRIBUTES); sa.lpSecurityDescriptor = &sd; sa.bInheritHandle = FALSE; const wchar_t* name = L"Global\\ShmTest"; HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, sizeof(SharedData), name); if (hMapFile == NULL) { qCritical("Error creating shared memory"); return 1; } data = static_cast<SharedData*>(MapViewOfFile(hMapFile, FILE_MAP_ALL_ACCESS, 0, 0, sizeof(SharedData))); if (data == NULL) { qCritical("Error mapping shared memory"); return 1; } HANDLE hPipe = CreateNamedPipe( TEXT("\\\\.\\pipe\\MyPipe"), PIPE_ACCESS_DUPLEX, PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE | PIPE_WAIT, PIPE_UNLIMITED_INSTANCES, 1024 * 1024, 1024 * 1024, NMPWAIT_USE_DEFAULT_WAIT, &sa); if (hPipe == INVALID_HANDLE_VALUE) { qCritical("Error creating named pipe"); return -1; } if (!ConnectNamedPipe(hPipe, NULL)) { qCritical("Error connecting to named pipe"); return -1; } checkPipe(hPipe); #endif
Last updated: 2024-02-02

Post by thysonfury on OPTO22 Groov Epic PR2 Modbus Comms Dropping out every 2 hours and 4 Mins ^{CODESYS Forge talk (Post)}
Hi after some assistance with an error on a Groov PR2 PLC. We have a few different communications set up as shown below: One Modbus TCP Slave Connection - ( Sending / Receiving Data from a PC ) Two Modbus TCP Master Connection - ( Reading Data from a UPS Panel and Reading Data Gas Chromatograph) One Modbus RTU Slave Connection 485 - (Reading Data from a fire and gas panel) One Modbus RTU Master Connection 485 - (Sending Data to a Telemetry Unit) All Licenses have been installed as per OPTO22 suggestions of the order below: Modbus TCP Master Modbus TCP Slave Modbus RTU Master Modbus RTU Slave When I check on License manager the RTU Master license seems to disappear on installing the RTU. (What ever reason I’ve been told this is “normal”). If I use Device License Read It will successfully read all the licenses correctly. Now the issue is every 2 hours and between 4. For what ever reason the communications seems to end and lock up for about 20 seconds. During this time even if I was logged into the PLC it would kick me off and I’d have to re type the password to enter. Most of the devices can handle this however the RTU flags up a communications failure at the SCADA and is raising alarms every 2 hours and 4 mins. We’ve had multiple people go through the code to check for anything obvious. Does anyone have any ideas?
Last updated: 2024-04-15

Post by thysonfury on OPTO22 Groov Epic PR2 Modbus Comms Dropping out every 2 hours and 4 Mins ^{CODESYS Forge talk (Post)}
Hi after some assistance with an error on a Groov PR2 PLC. We have a few different communications set up as shown below: One Modbus TCP Slave Connection - ( Sending / Receiving Data from a PC ) Two Modbus TCP Master Connection - ( Reading Data from a UPS Panel and Reading Data Gas Chromatograph) One Modbus RTU Slave Connection 485 - (Reading Data from a fire and gas panel) One Modbus RTU Master Connection 485 - (Sending Data to a Telemetry Unit) All Licenses have been installed as per OPTO22 suggestions of the order below: Modbus TCP Master Modbus TCP Slave Modbus RTU Master Modbus RTU Slave When I check on License manager the RTU Master license seems to disappear on installing the RTU. (What ever reason I’ve been told this is “normal”). If I use Device License Read It will successfully read all the licenses correctly. Now the issue is every 2 hours and between 4. For what ever reason the communications seems to end and lock up for about 20 seconds. During this time even if I was logged into the PLC it would kick me off and I’d have to re type the password to enter. Most of the devices can handle this however the RTU flags up a communications failure at the SCADA and is raising alarms every 2 hours and 4 mins. We’ve had multiple people go through the code to check for anything obvious. Does anyone have any ideas?
Last updated: 2024-04-15

Post by thysonfury on OPTO22 Groov Epic PR2 Modbus Comms Dropping out every 2 hours and 4 Mins ^{CODESYS Forge talk (Post)}
Hi after some assistance with an error on a Groov PR2 PLC. We have a few different communications set up as shown below: One Modbus TCP Slave Connection - ( Sending / Receiving Data from a PC ) Two Modbus TCP Master Connection - ( Reading Data from a UPS Panel and Reading Data Gas Chromatograph) One Modbus RTU Slave Connection 485 - (Reading Data from a fire and gas panel) One Modbus RTU Master Connection 485 - (Sending Data to a Telemetry Unit) All Licenses have been installed as per OPTO22 suggestions of the order below: Modbus TCP Master Modbus TCP Slave Modbus RTU Master Modbus RTU Slave When I check on License manager the RTU Master license seems to disappear on installing the RTU. (What ever reason I’ve been told this is “normal”). If I use Device License Read It will successfully read all the licenses correctly. Now the issue is every 2 hours and between 4. For what ever reason the communications seems to end and lock up for about 20 seconds. During this time even if I was logged into the PLC it would kick me off and I’d have to re type the password to enter. Most of the devices can handle this however the RTU flags up a communications failure at the SCADA and is raising alarms every 2 hours and 4 mins. We’ve had multiple people go through the code to check for anything obvious. Does anyone have any ideas?
Last updated: 2024-04-15

Post by brouwyka on JSONByteArrayWriter string result incorrect order ^{CODESYS Forge talk (Post)}
Additional note: When doing all additions to a JSON array one after another without additions outside the array inbetween (and no more additions to the array after an item outside the array has been added) - which is not a viable solution for us as we might add items to any of the arrays at any time, but we tested regardless to be thorough - we get the following result: { "id": "machine_1", "readings": [ { "temp_mid": 153.8 }, { "temp_mid": 98.3 } ], "status": "RUNNING" } This mostly matches our expected outcome, aside from the JSONByteArrayWriter not adding indenting before closing square brackets ("]") at all. That doesn't matter for JSON of course, as it's not sensitive to indenting, but it's still a bug regardless. Also, it adds an unnecessary newline between items in the array (at least when having an array of objects, we haven't tested with arrays of primitives). I also want to reiterate that this is not a viable workaround for the issue for us - we have to be able to add to any array at any time, which should be possible according to the docs, and we are 100% sure indexes are correctly being managed and built up by the JSONBuilder and our wrapper (to track the index of each array & the latest item added to each exactly to make use of the documented possibility to add anything anywhere in the JSON at any time as long as you keep track of the returned indexes) around it.
Last updated: 2026-06-10

Post by rmarco on Generic Variables and FDB ^{CODESYS Forge talk (Post)}
Hello everyone, I am running into a highly frustrating issue in the FBD editor regarding a Function Block with generic constants (VAR_GENERIC CONSTANT). I created a FB using ST, with a generic var, useful for having a variable sized array, as follows: FUNCTION_BLOCK Coil VAR_GENERIC CONSTANT maxEvents: USINT := 5; END_VAR VAR events: ARRAY[0..maxEvents-1] OF IEvent; END_VAR These FBs have also several methods. I declare them as follows in code: VAR coil1: CDL.Coil<(maxEvents:=1)>; END_VAR and when using them in ST, I have no problems. However, when trying to use them in FDB, I do not know how to do that, as some strange misalignment happens. Here's what happens: When I add the block to my FBD canvas and assign coil1 as the instance name, the compiler throws this error: 'coil1' is not an instance of 'CDL.Coil<(maxEvents:=1)>'. Same occurs when I try to instantiate blocks such as 'coil1.turnOn' or similar. Here is what I have already tried, none of which worked: - Deleting the <(maxEvents:=1)> parameter from the text inside the FBD box. - Deleting the block entirely, dropping an "Empty Box", and typing coil1 above it to let the IDE auto-complete and format the block. - Running a full "Clean All" and rebuilding the code. I am aware that I could bypass the graphical editor by calling it in Structured Text. However, I need to keep this logic compatible to FBD. Has anyone encountered this specific FBD parsing bug with generic variables? Thanks in advance for any insights. Best regards, Marco
Last updated: 2026-06-29

Post by bbm1995 on Camera RTSP Feed ^{CODESYS Forge talk (Post)}
Hi dgrard, I had the same issue for a long time, but on a WAGO webvisu. Now I'm glad that I can share my solution. I don't know if you are trying to use the webvisu or the target visu, but this works on webvisu: Get "go2rtc" and set it up according to the documentation. I'm running the Windows binary. Here's my example of the go2rtc.yaml config file (contains working example streams): api: listen: ":1984" # default ":1984", HTTP API port ("" - disabled) origin: "*" # default "", allow CORS requests (only * supported) static_dir: "www" # default "", folder for static files (custom web interface) tls_listen: ":443" # default "", enable HTTPS server tls_cert: "./SSL/fullchain.pem" tls_key: "./SSL/privatekey.pem" streams: # Streams with multiple links will fall back on the next link. ABUS TVIP48511: - rtsp://<username>:<password>@<hostname>:<port>/ch1/main - rtsp://<username>:<password>@<hostname>:<port>/ch1/sub # Diagnostic connections Kirchhoff Institute for Physics - Germany: http://pendelcam.kip.uni-heidelberg.de/mjpg/video.mjpg Blanton Bottling, Kentucky - USA: http://camera.buffalotrace.com/mjpg/video.mjpg Tokyo - Japan: http://61.211.241.239/nphMotionJpeg?Resolution=320x240&Quality=Standard Tampere Hacklab - Finland: http://tamperehacklab.tunk.org:38001/nphMotionJpeg?Resolution=640x480&Quality=Clarity Soltorget Pajala - Sweden: http://195.196.36.242/mjpg/video.mjpg Kaiskuru Skistadion - Norway: http://77.222.181.11:8080/mjpg/video.mjpg webrtc: listen: ":8555" #ice_servers: # - urls: [ "stun:localhost:3478" ] # username: "" # credential: "" Access the webinterface of go2rtc and get the link of your stream. Use the link as for your browser frame in the visualization. Depending on your device, you need to be able to access the file /etc/lighttpd/lighttpd.conf or /etc/lighttpd/webvisu.conf and change the contents similar to this one, otherwise you'll get CORS and CSP errors in the browser and you won't be able to view the stream on the webvisu: # Webvisu specific settings $SERVER["socket"] =~ port_webvisu_used_any { url.redirect += ( "^/webvisu/?$" => "/webvisu/webvisu.htm" ) $HTTP["url"] =~ "^/webvisu/?" { var.response_header_policy_webvisu = ( # CSP for WebVisu, allowing inline sources. "Content-Security-Policy" => "default-src 'self' 'unsafe-inline'; media-src *; frame-src *", # CORS for WebVisu, allowing any origin to access. "Access-Control-Allow-Origin" => "*", # Tell older browsers that this page can only be displayed if all ancestor # frames are same origin to the page itself. "X-Frame-Options" => "SAMEORIGIN" ) # Response header policy for WebVisu setenv.set-response-header = var.response_header_policy_webvisu setenv.set-response-header += var.response_header_policy_common }
Last updated: 2023-11-14

Post by jari-koivuluoma on Problem trying Net Base Services 3.5.15.0 TCP connection ^{CODESYS Forge talk (Post)}
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 critcho on WebVisu Numpad dialog - Dialogtitle not accepting string variable ^{CODESYS Forge talk (Post)}
I have a WebVisu page which is re-used for multiple types of gas; it displays the alarm thresholds etc. for one gas at a time. I have an array of structures holding the set-points for each of the gasses. I'm trying to change the dialog title for the value input pop-up (VisuDialogs.Numpad). The Dialogtitle is set to Gas_Alarms.HighAlarmActivationLevelDialog, which is a string(50): When the gas type is changed (page first loaded, or prev/next buttons), METHOD Gas_Alarms.Update_Display_Variables is called, to update the strings used for the dialog titles so it shows GasName High Alarm Activation Level (EngineeringUnits), e.g. CO2 High Alarm Activation Level (PPM): HighAlarmActivationLevelDialog := Insert(' High Alarm Activation Level ()', EngineeringUnits, 30); HighAlarmActivationLevelDialog := Insert(HighAlarmActivationLevelDialog, GasName, 0); (That's not where the problem is, I'm just explaining why I'm using a variable dialogue title.) The variables used are definitely strings, but i'm always getting the error: "The type of the dialog title must be either STRING or WSTRING". I've tried moving HighAlarmActivationLevelDialog etc. to the GVL and also changing them to WSTRING, I even tried adding them to the structure array, but I always get the same error. Clearing the dialog title for that element removes the error - so I'm confident it's not a phantom error caused by something else. But I should be able to add these titles, can't just nuke them all to make it work. The MinVal and MaxVal for the Numpad are called from the array, e.g. GVL.Gas_Alarm_Configs[0].ScaledValueMIN, they are not getting an error. I am using array indexes 1 - 5 for the gasses, when I load the form or change gas, I copy the selected index to index 0 of the array, and values from Gas_Alarm_Configs[0].[ALL] are displayed on the page. When they hit save, I copy Gas_Alarm_Configs[0].[ALL] to Gas_Alarm_Configs[CurrentGasIndex].[ALL]. (ALL just means every element, I can't figure out how to display an asterix in this question... :) ) I've searched online for variable title dialog, but not found anything to help. Thanks for your help!
Last updated: 2025-05-29

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