Simple Modbus 64bit Integer

[Oz_Ba]

I need to configure an analog point that combines four consecutive Modbus registers into one 64-bit integer value. Is there a native way to achieve this in Geo SCADA Expert?

Thanks.

[AndrewScott]

The simple Modbus analog point doesn't have a 64-bit integer data type, only 16-bit and 32-bit integers.

The only 64-bit data type is IEEE-754 double precision floating point.

See "Driver Reference > Modbus - Simple Driver > Configuring Analog Points > Configure the Modbus Point Properties" page in the help.

The closest I can think of would be to use two analog points with UDINT data type to read each half of the 64-bit integer and then use a logic program to combine the two halves into a "Long Long" or "Unsigned Long Long" variable object, but that's rather messy and a variable doesn't have the features of a point.

[BevanWeiss]

With 'smarter' Flow Meters (and similar devices like Power Meters) there is starting to get a reasonably large number of field devices that have 64-bit registers to hold totaliser values.

It would be ideal if GeoSCADA Expert did include a 'special' 64-bit Advanced Modbus Point (with 1234, 4321, 2143, 3412, register type ordering options for retrieval).. I guess it could just be an option under the current Advanced Modbus Analog point...  I can't recall the native datatype for the Point's .Value field...  if it's already 64bit then it should be fine... otherwise I guess that's the bigger challenge..

[gabarit]

As @AndrewScott said, to use two UDINTs but calculate them in Calcilation Analog Point.

[AndrewScott]

Both simple and advanced analog points (and calculated analog points) use IEEE-754 double precision floating values so they can't store a 64-bit integer value without introducing a conversion error., hence my suggestion of using a 64-bit variable rather than an analog point.

However, depending on the application, maybe a conversion error is acceptable so an analog point could be used.