Post by corriibme on Setting array values with JSON Utilities SL ^{CODESYS Forge talk (Post)}
It turns out that you can build JSON structures without ever calling the JSONBuilder function block directly. Instead, create a pointer to JSON.JSONData and invoke the necessary methods on its dereference. The parent object has a parent index of -1 (and an index of 0). EVERY other item (including keys, values, empty arrays and sub-objects) created by the setX methods needs the index to increase by 1. Then use the JSONByteArrayWriter FB to generate your JSON string
Last updated: 2024-05-23

Post by plunje on Sensor not set ^{CODESYS Forge talk (Post)}
A got a larger project but this very small example makes it clear. I have a button, and after it's clicked a lamp should flip on and stays on, and when the mouse-button is released it should stay on. When I try that in the PLC_PRG it works, but when I change it to a function block (seet attched demo proj) it isn't. I'm fairly new to PLC programming but are very experienced C# engineer, but this goes above my head...
Last updated: 2024-05-26

Post by swe-hob on call of a method of a function block in another program ^{CODESYS Forge talk (Post)}
Hi, Let's assume following: PRG_1 fb_1 : fbExample1; fb_1.method_1 do something... PRG_2 fb_2 : fbExample2; fb_2.method_2 if xTest then PRG_1.fb_1.method_1(); end_if; Is there a reason why runtime hangs when I call the method_1 in PRG_1 from a method in PRG_2? Both programs run in the same task. No chance that any other program calls the method. What I practically do there is that in the program PRG_2 I add a structed object into a buffer. In PRG_1 I just process the items in the buffer.
Last updated: 2024-06-03

Post by swe-hob on call of a method of a function block in another program ^{CODESYS Forge talk (Post)}
Hi, Let's assume following: PRG_1 fb_1 : fbExample1; fb_1.method_1 do something... PRG_2 fb_2 : fbExample2; fb_2.method_2 if xTest then PRG_1.fb_1.method_1(); end_if; Is there a reason why runtime hangs when I call the method_1 in PRG_1 from a method in PRG_2? Both programs run in the same task. No chance that any other program calls the method. What I practically do there is that in the program PRG_2 I add a structed object into a buffer. In PRG_1 I just process the items in the buffer.
Last updated: 2024-06-03

Post by trusty-squire on Read "Homed" status from EtherCAT drive ^{CODESYS Forge talk (Post)}
Hi, Is there a way to read the homed status from the EtherCAT drive directly? I am currently flagging the homed status on the succesful completion of the MC_Home function block, but I have had false triggers where the drive didn't actually execute the homing procedure but the MC_Home FB is marked as complete without error. I looked at other MC/SMC function blocks but the closest I can find is the "Homing" bit from MC_ReadStatus FB, but this doesn't show if the drive is succesfully homed, only that it's homing. Any guidance is welcome. Thanks!
Last updated: 2025-01-07

Post by elsmart on Sequential read and triggering of Modbs RTU channels in application ^{CODESYS Forge talk (Post)}
Hello I need some help understanding how to use Modbus RTU (COM port) in Codesys enviroment. I defined a Modbus Server device (slave) in device tree and added some channels to read from (function 3). Also I set trigering mode to Application. I have a POU in which I want to trigger each channel one after the other something like this (C code for better visualisation): for (int i = 0; i < channelsCount; i++) { triggerChannel(channelsArray[i]); // Start transmission while(channel.xBusy); // Wait for transmission to complete } I have found ModbusChannel function block documentation but examples are scarce. I don't understand how rising edge triggering works. What would be the best solution for achieving sequntial channel triggering? What is the common way to read multiple Modbus channels once every time a specified POU is executed?
Last updated: 2025-05-16

Post by qkkk on Device Scan ^{CODESYS Forge talk (Post)}
Hello all, I have developed a custom I/O driver in CODESYS that communicates via a Unix Domain Socket. In my DeviceDescription.xml, I have set up the following: <scan supported="true"> <scanfbinstance fbname="IOScanDevice"> The goal is to allow the user to scan for connected I/O modules from the CODESYS GUI ("Scan for Devices") and automatically populate the device tree with detected submodules.</scanfbinstance></scan> The function block IOScanDevice is implemented in the driver library and added to the main device's FB instances. However, when I initiate the scan from the GUI, nothing appears to happen the function is not executed. Is there an example project or driver (open source or from CODESYS Forge) that demonstrates a working custom scan implementation?
Last updated: 2025-05-26

Post by fefefede on Get the numer of day ^{CODESYS Forge talk (Post)}
Hello i tro to create a program to turn on or off the air condition in relationship temperature and numer of day. I can't get the number of day. I try this after installing SysTime library but this not work and have this error on debug ------ Build started: Application: Device.Sim.Device.Application ------- Typify code... Generate code... [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0032: Cannot convert type 'Unknown type: 'SysTimeCore(TRUE)'' to type 'TIME' [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0035: Program name, function or function block instance expected instead of 'SysTimeCore' [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0032: Cannot convert type 'Unknown type: 'DayOfWeek(CurrentTime)'' to type 'INT' [ERROR] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0035: Program name, function or function block instance expected instead of 'DayOfWeek' [INFORMATION] giorno_accensione_aria: PLC_PRG Device: PLC Logic: Application: C0181: Related position Build complete -- 4 errors, 0 warnings : No download possible PROGRAM PLC_PRG VAR Temperatura: UDINT; AriaCondizionata: BOOL := FALSE; CurrentDayOfWeek: INT; //Variabile Giorno CurrentTime: TIME; GiornoDellaSettimana: INT; DayOfWeek: INT; END_VAR CurrentTime := SysTimeCore(TRUE); // Ottieni l'ora corrente CurrentDayOfWeek := DayOfWeek(CurrentTime); CASE GiornoDellaSettimana OF 1: // Azioni per Lunedì 2: // Martedì se più 10° accend altrimenti spegni IF Temperatura >= 10 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 3: // Mercoledì se più di 50° accendi altrimenti spegni IF Temperatura >=50 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 4: // Giovedì se più di 40° accendi altrimenti spegni IF Temperatura >=40 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 5: // Venerdì se più di 50° accendi altrimenti spegni IF Temperatura >=50 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 6: // Sabato se più di 25° accendi altrimenti spegni IF Temperatura >=25 THEN AriaCondizionata := TRUE; ELSE AriaCondizionata := FALSE; END_IF 7: // Domenica sempre spenta AriaCondizionata := FALSE; END_CASE
Last updated: 2023-09-14

Post by pistola on Pause Tab Order ^{CODESYS Forge talk (Post)}
I'm programming an HMI, and on a settings page I have external buttons allow the operator to tab between various elements to select which one they want to adjust. I then use "Input Configuration" > "OnMouseClick" to select which variable to adjust. The problem is, when adjusting the variable the pointer will move to the other elements within the tab order. Is there a way to pause or prevent the pointer to move to the other elements when a variable is TRUE?
Last updated: 2025-03-17

Post by matt-s on HMI Pushbutton/Move Instruction ^{CODESYS Forge talk (Post)}
I have not gotten to the bottom of this yet no. I have double check that the variables are correct linked. When online with the program I can see the button and rung going true for the move instruction, yet it does not change. Forcing the bit in the program does change the value in Groov View. I am kind of at a loss here, especially since the other POU(For the pumps) does the same thing fine.
Last updated: 2024-02-02

Post by trusty-squire on Strange problem with the ‘MC_SetPosition’ function ^{CODESYS Forge talk (Post)}
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 opineiro on Stack overflow with really simple function ^{CODESYS Forge talk (Post)}
Hi, I have an issue with a function which sends a message through API Rest. I'm using a function from httpCLient library. I have tested this function inside a program and it works fine. But when I want to use it inside a function (so I can call it simultaneously from 2 different points on the main program) it gives a stack overflow error. In detail it says: "C0297 Stack Overflow on Main Task. Stack sizes... Call hierarchy:" I have simplified as much as I can the function, but I'm hitting a wall with this. Anybody has an idea of what's wrong? Thanks!
Last updated: 2024-09-16

Post by imdatatas on MC_CamIn did not work properly with SMC_FreeEncoder on SoftMotion 4.17.0.0 ^{CODESYS Forge talk (Post)}
Hello, I am facing a problem with the new Softmotion 4.17.0.0 version. Has anyone encountered a similar problem, what is the solution? I would be happy if you could share it. Problem description: -- "SMC_FreeEncoder" encoder axis is the master, -- The motor of the servo driver on the EtherCAT bus is the slave axis. -- When the MC_CamIn block executed, the InSync output is activated. However, although the master encoder axis position value changes, there is no movement in the slave servo axis! Test steps: 1-) EtherCAT servo axis installed, configured and motion test was performed with MC_Jog. No problem. 2-) Softmotion general axis pool > SMC_FreeEncoder was added and pulse amount configuration was performed. No problem. 3-) Incremental encoder actual count value was transferred to the "SMC_FreeEncoder.diEncoderPosition" variable as DINT under the ethercat task in every cycle and the encoder axis position value was observed. No problem. 4-) A simple CAM table with a 1:1 ratio was created under the project tree. (For example: Simply, when the encoder rotates 1 turn, the motor will rotate 1 turn.) 5-) The SMC_FreeEncoder axis enabled with MC_Power and brought to the StandStill state. 6-) The MC_CamTableSelect block was run with default input values ​​(all absolute) and only the Cam table name was specified. The Done output was seen successfully. No problem. 7-) The MC_CamIn block was activated with default input values ​​(absolute) and only the master encoder axis name, slave servo axis name, CamTableID input pins was specified and then "Execute" input set to TRUE. 8-) The InSync output information of the MC_CamIn block observed as TRUE. However, although the encoder axis value changed, the position value of the slave axis did not change at all, it did not move. It always remained at 0.0mm. 9-) When I repeated the same steps above, only changing the master axis to SM_Drive_Virtual instead of FreeEncoder and gave movement to the virtual axis, this time the slave axis moved successfully. However, when the same steps and operations are performed with the same IDE just downgrade SoftMotion version from 4.17.0.0 to 4.10.0.0, everything works normally and without problems as expected in MC_CamIn block with FreeEncoder master. (By the way, The used IDE version is Codesys V3.5 SP20patch3.) Best Regards Imdat
Last updated: 2024-11-11

Post by thecolonel26 on How to use FB_Init with nested Function Blocks? ^{CODESYS Forge talk (Post)}
Delete ME
Last updated: 2023-08-31

Post by mubeta on Strange problem with the ‘MC_SetPosition’ function ^{CODESYS Forge talk (Post)}
No errors in any condition. The function terminate correctly with the 'done' bit. Now I leave the machine and I don't know when I will be there again. The assumption you made I had considered. The operational limits of the axis are all fit for purpose, and this function should operate virtually without even noticing the motion limits. In fact in practice with the axis at low speed the function corrects any numerical value of the position in the range 0 ... 360° without any problem whatsoever in a single PLC scan cycle.
Last updated: 2025-01-10

Post by schnepper on Minor UI bug: cannot create SFC POU after creating a Function POU ^{CODESYS Forge talk (Post)}
After creating a Function POU, it is not possible to then create an SFC POU. Steps to recreate: * Create a new Function POU. SFC is not allowed for Functions, so SFC does not show in the Implementation language dropdown. * Click Add Object -> POU... Function is selected for Type. * Select Program * SFC is not present in the Implementation language dropdown
Last updated: 2024-05-23

Post by duvanmoreno24 on Modbus writing on value change ^{CODESYS Forge talk (Post)}
Hi all, I want to know if someone has an idea of how I can write on value change in Modbus Codesys. I have a Wago PLC and I was used to work with E-cockpit which it was quite easy to do that without the necessity to trigger any value when there was a change in the variable ( I will put how easy is ). how you can see just changing the trigger in "On value Change" will do that channel writing automatically when It detects a change in those arrays. On the other hand, in Codesys if I enable the rising edge in Codesys It ask me to put a bool variable and if triggers is going to write that value. That is making me that I have to create a function or a logic to detect the change, the problem I have is that doing that is very tedious. I first approach I got it was to create a Function who returns a bool when the value change, but I tried to keep the old value but what is happening is that in Functions all the data is erased every cycle so I can not keep any Old value. so in the Main program the trigger is going to be TRUE all the time due, the old value is cero every cycle. The second approach I got it was using a function Block (POU_1) and it works but I dont want to instance that function for every Channel or value that I want to check if the value change, Basically if I have 200 values to write trhough modbus I have to create 200 instances of that function which I think it is not practicall at all. It should be a better way to implement this as e-Cockpit from Wago Does. However, I haven't been able to know how.
Last updated: 2024-03-26

Post by timvh on Get Alarm status in Codesys ^{CODESYS Forge talk (Post)}
You are right, that you can use the GetState method, but it is not that simple. You first have to get a list of (filtered) alarms from the AlarmManager. You can find an example in Forge how to do this. See https://forge.codesys.com/prj/codesys-example/alarm-manager/home/Home/ Then you can go through this list to get the state of all the (filtered) alarms. See below the code which you could use. This is all based on the example from forge. Create a program: // This example shows how to access alarms via structured text. PROGRAM PLC_PRG VAR xInit : BOOL := TRUE; udiResult : UDINT; fbAlarmFilterCriteriaAll : FB_AlarmFilterCriteriaAll; fbAlarmManagerClient : FB_AlarmManagerClient; itfAlarmManagerClient : IAlarmManagerClient := fbAlarmManagerClient; xAlarm1 : BOOL; xAlarm2 : BOOL; xWarning : BOOL; iNrOfAlarmsInAlarmList : INT; iNrOfActiveAlarmsInAlarmList : INT; paitfAlarm: POINTER TO ARRAY [0..0] OF AlarmManager.IAlarm; iAlarmIndex : INT; eAlarmState: AlarmManager.AlarmState; END_VAR IF xInit THEN xInit := FALSE; fbAlarmManagerClient.itfAlarmFilterCriteria := fbAlarmFilterCriteriaAll; // register alarm client to get updated about alarm status / changes udiResult := AlarmManager.g_AlarmHandler.RegisterClient(itfAlarmManagerClient, 0, 0); END_IF // Polling the number of alarms udiResult := AlarmManager.g_AlarmHandler.GetActiveAlarms(itfAlarmManagerClient, parritfActiveAlarms => paitfAlarm, iCountActiveAlarms => iNrOfAlarmsInAlarmList); iAlarmIndex := 0; iNrOfActiveAlarmsInAlarmList := 0; WHILE iAlarmIndex < iNrOfAlarmsInAlarmList DO eAlarmState := paitfAlarm^[iAlarmIndex].GetState(); IF eAlarmState = AlarmManager.AlarmState.Active OR eAlarmState = AlarmManager.AlarmState.ActiveAcknowledged THEN iNrOfActiveAlarmsInAlarmList := iNrOfActiveAlarmsInAlarmList + 1; END_IF iAlarmIndex := iAlarmIndex + 1; END_WHILE See below some details about the function blocks: One function block should implement the IAlarmFilterCriteria interface. This can be empty except a few methods. FUNCTION_BLOCK FB_AlarmFilterCriteriaAll IMPLEMENTS AlarmManager.IAlarmFilterCriteria Method implementation (others related to interface are empty) METHOD AreAllAlarmClassesSelected : BOOL AreAllAlarmClassesSelected := TRUE; METHOD AreAllAlarmGroupsSelected : BOOL AreAllAlarmGroupsSelected := TRUE; METHOD GetPriorityFrom : USINT GetPriorityFrom := 0; METHOD GetPriorityTo : USINT GetPriorityTo := 255; The other function block should implement IAlarmManagerClient and get a reference to the FB which implements the IAlarmFilterCriteria FUNCTION_BLOCK FB_AlarmManagerClient IMPLEMENTS AlarmManager.IAlarmManagerClient VAR_INPUT itfAlarmFilterCriteria: AlarmManager.IAlarmFilterCriteria; END_VAR Method implementation (others related to the interface are empty) METHOD GetFilterCriteria : AlarmManager.IAlarmFilterCriteria // see VAR_INPUT for filter GetFilterCriteria := itfAlarmFilterCriteria; Off course you have to add the AlarmManager to your application and add some alarms to it.
Last updated: 2025-09-02

Post by e13740e on Parameterized Property syntax for array element processing ^{CODESYS Forge talk (Post)}
Since parameterized (indexed) properties are not possible, I decided to use architectural approach "Indexing Property Adapter" to achieve the intended goal — avoiding code duplication for validated access to array elements. Essence: Create a Function Block Adapter (FB_PropertyAdapter) that encapsulates the logic for working with a single element of the target array (e.g., with one settings structure). Declare Properties inside the adapter block for accessing each individual field of the data structure. All validation logic is implemented within the Set accessors of these properties. Data Binding via VAR_IN_OUT: The adapter block receives a reference to a specific data element from the global array through its VAR_IN_OUT section, which ensures direct work with the original data without copying. Create an Array of Adapters: In the parent POU (e.g., FB_SettingsManager), an array of these adapter blocks is created — one for each element of the global array that needs to be managed. Initialize Bindings: In a FOR loop, each adapter instance from the array is given a reference to the corresponding data element. Result: This approach allows accessing the data via the index of the adapter array, and then through the property name, which simulates the behavior of an indexed property: MyAdapterArray[Index].MyProperty Thus, the validation and data access logic is written only once inside the adapter block and is then reused multiple times by creating instances of it in an array. This completely solves the problem of code duplication while providing a clean, scalable, and object-oriented architecture compatible with standard CODESYS features. Question closed.
Last updated: 2025-10-19

Post by anhkdv on Motion FB Error ^{CODESYS Forge talk (Post)}
Hi! I'm a newbie. I'm doing a project for Delta Robot using Codesys and got this error when trying to move in a dynamic coordinate system. This error occurs when I use FB MC_MoveLinearRelative and FB SMC_GroupWait
Last updated: 2023-10-08

Post by trycyclepower on How to set unit in Axis ^{CODESYS Forge talk (Post)}
I am very new to Motion in Codesys. I have linear axis and would like to setup as mm, I want to move axis and control axis in mm, mm/s. How do I do that? I know my electronic gearing is 200000.
Last updated: 2024-08-29

Post by mucleus on How to implementation Gantry Robot path. ^{CODESYS Forge talk (Post)}
Hello. How can I move path like in the attached image using CODESYS's robotics library? (MC_MoveLinearAbsolute, MC_MoveDirectAbsolute, MC_MoveCircularAbsolute, etc.) Please help me. Thanks.
Last updated: 2025-02-13

Post by davidbo on Why is Application_DataLog.sqlite not moved to my directory ^{CODESYS Forge talk (Post)}
In CODESYScONTROL_User.cfg I have [SysFile] FilePath.1=/etc/, .dat FilePath.2=/home/pi/DataLog/, .sqlite, .sqlite.metadata, .sqlite-journal, .sqlite.tmp PlcLogicPrefix=1 Should that not write the Application_DataLog.sqlite in the /home/pi/DataLog/ directory? Or how do move the working directory for AC_Datalog ?
Last updated: 2025-08-22

Post by pr0schwein on Driving the slave axis across master's zero point - caming ^{CODESYS Forge talk (Post)}
Is there a way to move the slave axis across the zero point of the master axis with variable start and stop points? For example: Slave start at 270° and end at 50°. thanks :)
Last updated: 2024-01-18

Post by matt-s on HMI Pushbutton/Move Instruction ^{CODESYS Forge talk (Post)}
I know, that is not the issue though. The issue is the HMI_Blower_Auto_PB variable not changing to false. I do not have the IO modules plugged in yet, that is why there are NaN values for those variables. That should not affect this.
Last updated: 2024-01-25

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