Modbus TCP/IP driver. Adding LLong data type tags.

[AG_14406722]

Hello everyone,

I’m trying to configure a tag of type LLong (Signed 64-bit Integer) in KEPServerEX 6.18 for a Modbus TCP/IP device, but I’m running into an addressing issue.

My setup:

• Channel: Modbus TCP/IP Ethernet
• Device: Custom Modbus server running on Raspberry Pi (C#)

The server exposes a 64-bit signed integer, stored correctly on the Modbus side.

When I attempt to add a tag with data type LLong, KEPServerEX refuses any register address I enter. I’ve tried:

• 40007
• 400007
• 30007
• 300007

But I always get the same error:

“Data type 'LLong' is not valid for address '400007'.”

It looks like KEPServerEX does not accept any Modbus register address for this data type, and I’m not sure whether the issue is related to:

register type selection (3x/4x),

addressing mode (1-based / 0-based),

strict syntax rules,

or a limitation of the Modbus TCP driver regarding 64-bit values.

My questions.

1) Has anyone successfully configured an LLong (64-bit) tag in a Modbus TCP/IP channel?
2) What is the correct address format for such a tag?
3) Are any specific driver settings required?

Any guidance or examples would be greatly appreciated.

Thanks!

[rajskumar]

Hello, Please take a look at the following article as it may help resolve your issue:

CS310966 - How to read a 64 bit value from Modbus device in PTC Kepware Products

If you are prompted to log in to view the complete article, you can use your MyKepware login credentials. Thanks 

[MRohilla · Accepted solution]

Greetings,

Hello, Please take a look at the following article as it may help resolve your issue:

CS310966 - How to read a 64 bit value from Modbus device in PTC Kepware Products

If you are prompted to log in to view the complete article, you can use your MyKepware login credentials. 

Thanks