No way to read a undefined floating point value through KEPServerEX?

[Tanquen]

When using drivers with HMI applications like InTouch or Ignition, the tag in its database could have address modifiers or simply the tag type to let the Modbus driver know that you're looking for a floating point that is using more than one register.

It appears that there's no way to accomplish the same thing when using KEPServerEX. Instead of a Modbus driver specifically written for Intouch or Ignition HMI applications.

The only option is to manually create tags inside of KEPServerEX and then read those from the HMI? 

[rajskumar]

Hello,

Are you looking to define tags directly in the client instead of creating them in KEPServerEX?

If yes, you can use dynamic tag addressing to retrieve data in the client without defining tags in the Kepware server. Here is an article that clarifies the difference between static and dynamic tags.

CS278481 - Differences between static and dynamic Tags in KEPServerEX / ThingWorx Kepware Server

Thanks

[Tanquen]

Yes, we were hoping to reference Modbus TCP/IP values without having to define tags inside KEPServerEX, but it looks like if we want a floating point that uses two registers there's no way to do this without creating a point inside KEPServerEX. Drivers provided by the HMI manufacturers normally have a way to do this.

That article kind of makes it look like you can with the data type modifier ?

Article - CS278481

• Most OPC clients allow users to specify the data type as part of the request when registering a link for a specific data item. The data type specified by the OPC client is used if it is supported by the communications driver. The @[Data Type] modifier can be useful when ensuring that a communications driver interprets a piece of data exactly as needed

[Tanquen]

Seems not to work for Ignition and the KEPServerEX Modbus TCP/IP driver.

When the address includes '[]' there is an error.

`PLC.40007@[Float] ` 

The example they give in the manual `Channel1.Device1.R0001@Short` doesn't have the square brackets so it may just be the Modbus TCPIP driver doesn't support it.

[rajskumar]

It seems you only added the device or channel name and then the tag address. To pass a dynamic request, you need to include both the channel name and the device name, and then append the data type.

[Tanquen]

Sorry, that was just an example.

I was mainly concerned with the correct formatting of the data type suffix. I did see in the manual that the square brackets are not included. When we do not include the Square brackets there's no error and we do get a value but it's the same value with or without adding the data type.

So now we're wondering if maybe this data typing is not supported by Ignition or the KEPServerEX Modbus TCP IP driver?