ModbusTCP Server Real (datatype) Problem

_andi_

Hi,

I'm using Mervis RT, setting up a modbustcp slave (also called server). When I add a variable of type real and choose "Identity" as conversion method I get one Int on the bus instead of two. Is this a known issue or am I missing some setup?

Thanks, Andi

tomas_hora

Hello @_andi_ ,

can you please share the project with us? Zip the whole project folder and upload it somewhere if possible so we are clear on what you want to achieve.

_andi_

Hi,

thats what I'm, doing. Just having the real works fine, adding the int breaks the real.

https://drive.google.com/open?id=1W7ZJpO1MUiSXMdvRWszUj2BQtqj9uxx2

Thanks, Andi

Martin Kudláček

Hi @_andi_ ,
the real value is 32bits long, that means it will take two registers, in your example registers 1 and 2. By adding register 2 with variable "int1" you have inadvertently overwrite the half of the previous register. To avoid that, set the starting element of the "int1" to 3.

_andi_

Ah, thanks! I just clicked "add variable" and didn't realise I can / have to actually edit the offset afterwards. Might be worth a feature request to change the gui to automatically check the previous value and adjust the starting element accordingly.

Martin Kudláček

@_andi_ Noted:)