Citect Modnet initvariable for 32bit-only devices

[kor]

I have a problem with connect to Citect  Modbus device ( network analyser ), this particular device allow only 2 and multiply 2 length readouts for registers. All request for 1 or odd length registers will provide exception code because all device memory is 32 bit organised.

In the MODNET I can't force use 2 register (long ) readout for init variable, in documentation there is present only 'initvariable' parameter but it's related to choose between (holding/input registers an so one ) but to ti force read at least 2 word instead 1 as Modnet driver does.

There is a way to force init device request as 2 word length?

[PV_DAQ]

I ran into a flowmeter that defaulted to 32 bit floating point memory architecture, similar to what you describe for the network analyzer, but discovered that a configuration variable allowed for the choice of "Modicon standard", the conventional Modbus memory architecture with standard 16 bit word registers: Integers for 16 bit single word registers, floats need 2 contiguous registers.

Can the network analyzer be configured for standard Modbus operation?

[kor]

Unfortunately, my analysers has only the one data and memory format 32bit  

[PV_DAQ]

Can you post a link to the Modbus documentation for the device?

[kor]

Please find attached here: Frer modbus docs 

[PV_DAQ]

I don't understand exactly what your problem is. Modbus functionality appears to be conventional on this slave device.

Some variables are 16 bit, single Modbus register integers, some are 32 bit, two Modbus register long integers.

The slave supports FC03 to read Holding registers and FC16(h) to write to holding registers.

The slave does not allow a read or write to only half of a multi-register variable, which is for your own good, so you don't get meaningless data.

Which variable (register number) are you trying to read or write that you can't?

[kor]

All variables are 32 bit, as I've wrote analyser will't answer if we've asked about one register from 32 bit pair.

[PV_DAQ]

 I can't help if you don't provide actual details, sorry.