Hi,
I try to read string tag via the flexy. Unfortunately The other topics say it’s not possible but it was at least 2 years ago. So my question is: is it still impossible to read string tag with modbus TCP comunication ?
thanks in advance
Hello,
We do have a tech forum post that goes over a the procedure to read a String Tag with Flexy.
https://techforum.ewon.biz/thread-169.html
I would review the post above, and let me know if that resolves your issue.
As of now, the Flexy does not have the native capability to read a String tag through Modbus. It will require some BASIC IDE scripting and Tag manipulation.
We do not have an official release for when this feature will be implemented with the Flexy.
To add to this, the issue is more that modbus does not offer a string data type. Modbus is designed to read/write 16 bits of data with registers or bits via coils. A sting is an array of 8 bit characters. To get a sting via modbus you need to read a set of registers then break the data up into 8bit chunks to be interpreted as a string. The Techform Kevin shared uses the Basic IDE to setup a modbus read request for multiple registers then breaks out the characters and building a string.
Thanks for you answer.
This solution seems a bit complicated for my abilities.
Do you have any idea what COM I can use to send/receive string tags? I use an M251 from schneider for comunicate with the flexy
We have built in string support for Allen Bradly PLC’s and Siemens.