# Help Needed: Reading Modbus Serial Data on 750-8208 Using CODESYS 2.3 and Sending to Cloud
**URL:** https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779
**Category:** CODESYS
**Created:** [April 23, 2025, 7:05am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779 "2025-04-23T07:05:48Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@Mehak\_Fatima](https://www.wago.community/u/Mehak_Fatima)
#### Post date: [April 23, 2025, 7:05am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/1 "2025-04-23T07:05:48Z")
Hi everyone,
I’m working on a project using the **WAGO 750-8208 controller** , and I’m currently stuck at a critical point.
Previously, while using **e!COCKPIT** , I was able to use the **Modbus Serial Master library** to read data from Modbus devices over the serial port without much trouble.
Now, I’ve moved to **CODESYS 2.3** , and I’m trying to achieve the same thing— **read data from a Modbus serial device** —but I’m not sure if the equivalent library exists in CODESYS 2.3 or how to implement it. I’ve looked around, but couldn’t find a clear answer or example.
Once I can successfully read the data, my next step is to **send that data to the cloud** (exact method/API still to be decided), but I can’t proceed until I can reliably access the serial data.
Has anyone here worked with Modbus Serial in CODESYS 2.3, especially on the 750-8208?
- Is there a compatible Modbus Serial Master library?
- Any example projects, documentation, or tips you could share?
- Bonus: If you’ve sent this kind of data to the cloud, how did you handle that?
Really appreciate any help or direction you can provide. Thanks in advance!
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### Author:  [@Thruser](https://www.wago.community/u/Thruser)
#### Post date: [April 23, 2025, 8:12am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/2 "2025-04-23T08:12:04Z")
Hi,
there is the Modb\_l05.lib with similar function blocks.
For Codesys 2.3 Wago has also implemented a modbus configurator. There should be also a document on wago site.
In Codesys go to the Ressources tab, then PLC Configuration. Under Modbus-Master[FIX] you will find the configurator.
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### Author:  [@Mehak\_Fatima](https://www.wago.community/u/Mehak_Fatima)
#### Post date: [April 23, 2025, 8:34am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/3 "2025-04-23T08:34:56Z")
Thank you for the response…
If you are talking about this then it will take lot of time to use as single register again and again.
Any help regarding cloud connectivity
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### Author:  [@Thruser](https://www.wago.community/u/Thruser)
#### Post date: [April 23, 2025, 9:11am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/4 "2025-04-23T09:11:30Z")
Hi,
on context menu of the variable you can find ‘number of items’, with this you define an array.
With the modbus configurator you need to declare a task for your main program. PLC\_PRG will only run automatically if no other task is configured.
With cloud connectivity I have no experience.
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### Author:  [@WagoIcard](https://www.wago.community/u/WagoIcard)
#### Post date: [April 25, 2025, 4:50am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/5 "2025-04-25T04:50:47Z")
For Cloud connectivity you have some sample program on the WAGO Website:
> **[WAGO | 15719](https://www.wago.com/global/d/15719)**
>
> This application note explains how the WAGO controllers PFC100 and PFC200 can communicate with cloud services like Microsoft Azure (WAGO Cloud), Amazon AWS and IBM Bluemix. Data could be send to the cloud and commands could receive from the cloud....
and there is this library on the site too but i have no idea if this one is not older than what you already have:
> **[WAGO | 16179](https://www.wago.com/global/d/16179)**
>
> Die Bibliothek dient zur Kommunikation des WAGO Controller PFC100 und PFC200 mit Cloud Diensten wie Microsoft Azure (WAGO Cloud), Amazon AWS and IBM Bluemix. Daten können zur Cloud gesendet und Kommandos von der Cloud empfangen werden.
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### Author:  [@Mehak\_Fatima](https://www.wago.community/u/Mehak_Fatima)
#### Post date: [April 25, 2025, 9:48am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/6 "2025-04-25T09:48:57Z")
Thank You @WagoIcard for the reply.
I am facing this error while downloading the program on the PFC
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### Author:  [@WagoIcard](https://www.wago.community/u/WagoIcard)
#### Post date: [April 28, 2025, 12:20am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/7 "2025-04-28T00:20:59Z")
What FW are you running in the PFC200 ?
in the main web page of the PFC200 you should have a FW number something like this:
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### Author:  [@Mehak\_Fatima](https://www.wago.community/u/Mehak_Fatima)
#### Post date: [April 28, 2025, 3:38am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/8 "2025-04-28T03:38:29Z")
I have firmware 22 running on the controller.
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### Author:  [@WagoIcard](https://www.wago.community/u/WagoIcard)
#### Post date: [May 8, 2025, 6:13am UTC](https://www.wago.community/t/help-needed-reading-modbus-serial-data-on-750-8208-using-codesys-2-3-and-sending-to-cloud/1779/9 "2025-05-08T06:13:48Z")
Conversation moved to
[https://www.wago.community/t/unresolved-external-pous-error-on-750-8202-8-with-cloud-library/](https://www.wago.community/t/unresolved-external-pous-error-on-750-8202-8-with-cloud-library/)