Modbus RS 485 Communication with Radix instrument(Process Variable of floating point type)

[nnarra]

Hi all,

I am facing one problem while communicating with Radix Instrument using Modbus RS 485 Interface.can anybody help me in this,

The instrument which i am going to communicate is Radix ISOSCAN(16 Channel Temperature Scanner).

The instrument is having Modbus RS 485 interface facility.

To that instrument,RS 485 Configuration is there.And I am using RS 485 to RS 232 Converter for communicating with my PC.

I downloaded Modbus VI Library from NI and I programmed using Modbus VIs.

I got the instrument Register Addresses also.From this instrument,I want to read 16 channel temperature values.For this,in Modbus terminology we will call as Process Variables(PV).

For this,I used Read Input Registers(Function Code 04) and I have doubt in configuring Starting Address terminal of "MB Serial Master Query.vi".Because,here if we see the datatype of this terminal,it is U16.But if we see the Instrument register addresses,it is of floating point type.

Can anybody help how can i go further ...,

Regards,

bujjin

[cs_BOT]

Hi,

 Is your floating point number 32 bit or 64 bit or 128 bit??

Modbus Library in LabVIEW accepts only 16 Unsigned Integer so you would have to programmatically get the number. I suggest use "join numbers" function (Programming >> Numeric >> Data Manipulation >>).

Also you can monitor what kind of data you are recieving using hyperterminal or Portmon to get a clear idea.