Post by davidbo on I2c write is BeforeWriteOutputs needed? ^{CODESYS Forge talk (Post)}
I have made an I2C library where writing happens by calling write8 I now see that I do not call BeforeWriteOutputs at all, however it seems to work data are sent at least for an hour. So is BeforeWriteOutputs needed
Last updated: 2024-02-07

Post by mondinmr on Direct Pointers in IOMapping for EtherCAT with IoDrvEthercatLib.ETCSlave_Dia ^{CODESYS Forge talk (Post)}
Using SDO, I can read the EtherCAT mappings and offsets from various registers like 0x1c12, 0x1c13, etc. When I obtain registers mapped in the PDOs and various offsets, I could technically access directly to the statusword, controlword, etc., if they are mapped. I have noticed that on IoDrvEthercatLib.ETCSlave_Diag I can find pointers to the input and output buffers. However, although the input buffer can be easily read by referring to what has been obtained from the SDOs, it is not possible to write to the output buffer, as it is overwritten in each cycle by the data from the IOMapping task. Is there a way, knowing an instance of IoDrvEthercatLib.ETCSlave_Diag, to obtain the pointer to the first data in the IOMapping? The offsets are identical to those of the PDOs, but obviously the data is a copy. For me, the cleanest thing would be to access the pointers on IOMapping, for DS402a devices to retrieve the key data and point them to internal references. I need to know this as, having developed our own motion library, I would like to simplify the initial setup by eliminating unnecessary and nonsensical mappings that can lead users to unnecessary errors. In the current version that we have been using for years, we have to map everything manually. I would like to pass only the slave reference to the FB_init constructors and eliminate the mapping.
Last updated: 2024-02-12

Post by paro on OPCUA array max length? ^{CODESYS Forge talk (Post)}
I think the amount of data is already relatively high and maybe it has something to do with that? Maybe also the CPU load of your device? an array with string(5000)? and have you tested with how many array elements it still works?
Last updated: 2024-02-17

Post by sumit on Not able to see input data coming from eip adapter on codesys ^{CODESYS Forge talk (Post)}
Yes, green icon is there, this time I tried by enabling the device to always update variables but results are the same. I have attached the screenshot and eds file I am using.
Last updated: 2024-03-06

Post by rckalex on Data Source Limit ^{CODESYS Forge talk (Post)}
There appears to be a limit to the number of OPC Servers that can be connected simultaenously. 1-10 work but adding an 11th makes one of the previously linked ones unavailable. Is this a soft setting that can be adjusted? Using 3.5.18.30 on Win x64
Last updated: 2024-03-06

Post by rckalex on Data Source Error 418 ^{CODESYS Forge talk (Post)}
Trying to connect to a Codesys V3 datasource but am unsuccessful. The error information for the datasource reads: Failed (not nearer specified) Error ID: 418 Can anyone shed light on what that error means?
Last updated: 2024-03-06

Post by sumit on Not able to see input data coming from eip adapter on codesys ^{CODESYS Forge talk (Post)}
i-campbell, Thank you the suggestion, issue was the windows firewall not allowing the UDP traffic to pass through for EIP. thanks again
Last updated: 2024-03-07

Post by thewizard8 on Raspberry PI4 Serial Port ^{CODESYS Forge talk (Post)}
Hi thanks once again, Yes it supports because using python scripting I'm able to send data from the rasberry raspberry and receive it on my pc and vice versa (Image attached). But when using the CoDeSyS I just got red flags. Any light on this problem?
Last updated: 2024-03-19

Post by kislov on Remove white spaces in file .txt ^{CODESYS Forge talk (Post)}
Seems like you use SIZEOF as size, but you need to use LEN as size of data which you want to write.
Last updated: 2024-04-23

Post by kevinm on Data source and safety PLC ^{CODESYS Forge talk (Post)}
I am having the same trouble. However, if I change the Login Configuration settings to 'Type: Login using the credentials determined at runtime' then the Connection information continues as 'Connection state: Connecting' and 'Error information: OK'. There is no User Management on the source PLC.
Last updated: 2024-05-16

Post by ignat on [SOLVED] Safety EL6900 - SELC0012 Invalid number of connections[ ^{CODESYS Forge talk (Post)}
Hi kurvanov, could you please share the video you mentioned. I am struggling with basic data intechange between safety module and basic plc logic
Last updated: 2024-06-17

Post by kporter on SoftMotion, accessing PDO input data via object ref/pointer ^{CODESYS Forge talk (Post)}
It looks like one can use the OutputData and InputData members of ETCSlaveStack: https://content.helpme-codesys.com/en/libs/EtherCATStack/4.2.0.0/EtherCATStack/ETCSlaveStack.html
Last updated: 2025-10-29

Post by ranadheer on conformation about the CODESYS Extends SL and CODESYS SDK ^{CODESYS Forge talk (Post)}
hello everyone would anyone here respond, Is CODESYS Extends SL and CODESYS SDK are same. If both are not same could you please give related data about this. Best Regards Ranadheer
Last updated: 2025-11-10

Post by unusual-data on C0138: No matching 'FB_Init' method found for instantiation of VisuClientObjectMgr ^{CODESYS Forge talk (Post)}
you can try to disable "Visualization Manager - Settings - Support client animations and overlay of native elements " selection" It worked for me, thank you.
Last updated: 2025-12-18

Post by tjacks on Opc UA Data Source Client Browse Error in Codesys HMI ^{CODESYS Forge talk (Post)}
Codesys V3.5 SP21 Patch 3 Codesys HMI 3.5.21.30 I'm trying to connect to an OPC UA server on a Kuka robot controller using Codesys HMI's data source manager. I get through the login phase and the client browses most of the data structure on the server but errors out toward the end with a generic: Error while browsing the client, Failed with service result: BadUnexpectedError. If I complete the data source setup and try to update variables, I get the attached stack trace for the error. I've tried several different endpoint and security options. Most get me through the login but all error out while browsing. UA Expert happily connects and browses with the same configuration. I've connected this same version of Codesys to TwinCAT OPC UA servers and Siemens PLC OPC UA servers. Any ideas on what may be causing the generic BadUnexpectedError during OPC UA server browse?
Last updated: 2025-11-17

Post by ketanvaishnav on Redundancy Codesys Runtime, Synchronization ^{CODESYS Forge talk (Post)}
i am facing same data sync issue. i am use two 750-8212 (FW30) controllers. datas are sync from active to standby during changeover time, but datas are not sync from standby to active.
Last updated: 2026-01-30

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 janderson on OPC UA Server limitations, large array crashes runtime ^{CODESYS Forge talk (Post)}
What are the limitations of the OPC UA Server? I am trying to get data off my PLC that is acquired at high rates (~50k samples/s) so I am storing them in arrays and trying to get the arrays off the PLC. When I attempt to read a ~200k element array through OPC UA the server and runtime crashes (requiring tools -> update linux arm64 -> start runtime). Is there a better way to get highspeed data off? The ACDatalog library seems a bit irritating to use so I would prefer to go through OPC UA.
Last updated: 2023-08-23

Post by peterned on Programatically restart Codesys OPC UA server? ^{CODESYS Forge talk (Post)}
Hi, I'm using a Festo Codesys PLC (CPX-CEC-C1-V3), which is connected to a HMI panel. Both exchange data via OPC UA. Occasionally, the HMI stops displaying data, and looks as if there is no connection. If the HMI stops, the only way to make it work again is to restart the PLC. Restarting HMI has no effect. When the PLC is restarted, HMI starts working normally again. Is it possible to restart the OPC UA server from PLC code? I hope this will make fixing the HMI possible without a PLC restart. Thanks
Last updated: 2024-07-19

Post by peterned on Array to String ^{CODESYS Forge talk (Post)}
max. string length in Codesys is 255 chars. It's not possible to cram 20,000 things in a string. If you need to send the data to another device, send the whole data[] array (as byte array, without doing anything to it) and extract the information on the other end. As each struct member has a fixed size (81 bytes, as per you declaration), this will be easy. To save some resources, consider declaring string lengths - e.g. if the max possible length for key is 10 chars, declare it key: STRING(10); and it will occupy 11 bytes instead of 81
Last updated: 2024-07-20

Post by dawidr on Best practices for querying multiple MODBUS devices ^{CODESYS Forge talk (Post)}
Hi! What are the best practices for querying multiple Modbus devices? Single PRG or maybe multiple PRG (so basically multiple thread) per each Modbus device. In my current implementation I'm using single PRG and I'm utilizing FbMbMasterMultiQuerySerial and WagoAppPlcModbus.FbDigitalTwinMbSlaveDevice in eCockpit with PFC200. I've the timer with 2 seconds delay there and it was working fine for single device. But now I have three Modbus devices and for two of them I need to run 2/3 queries to get data from all registers. I noticed that the delays for getting the data from the Modbus devices is much bigger right now.
Last updated: 2024-07-31

Post by expertplas on No connection to opc server from codesys opc client ^{CODESYS Forge talk (Post)}
Hello, we have aproblen to connect our CODESYS OPC Client to the OPC Server. We installed the client according the CODESYS manual. We can browse the server and variables can be linked to the PLC. I created a self signed certificate for the CmpOPCUAClent as described. The server has a cerificate also. I copied the certificates to the trusted zone of server and client. But when it comes to data exchange we get an error message. "Communication error in data source OPC UA Library. Error ID : 7001 German : "Kommunikatinsfehler inder Datenquelle OPC UA -Bibiothek. Es wurde kein genauer Fehler angegeben. Fehler ID : 7001" It semms that there is no cerificate exchange. We are working with CODESYS 3.5 SP19 Patch 5. Can anyone here say something about this error or has an idea for a solution? Thanks.
Last updated: 2024-08-19

Post by trent on Automation server - trends stop recording - need to manually reconnect ^{CODESYS Forge talk (Post)}
Hi All, I use the analysis page in automation server to capture historical trends from my PLC - i only sample one point per hour but it does the job (for now) One issue I have is I often log on to analysis page to find the system has stopped recording trends from my PLC. To fix this, I need to choose "state information" in the "List view" under PLC and click "Reconnect" When I do this I see my variables listed under "parameters" under "PLC Details" start updating again and the trend in Data analyzer continues to update. My Question, Why do I need to manually reconnect? Is there a way to get automation server to automatically reconnect to the PLC so I continue to capture data from the PLC? Regards, Trent
Last updated: 2024-10-22

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