I am trying to write a Lab View VI to record data to a spreadsheet.  All of the analog inputs are in the same while loop, and record data at the same rate, to an array, so all the data is synchronize.  The only element left is a balance that is connected by a USB to RS-232 serial connection. The scale is recognized by VISA.  I would like to put the scale input and writing in the same while loop as all of the analog data so I get one datapoint from each instrument at the same time. I also want it to write to the same (floating point string )array as all of the other data. I know nothing about the protocols associated with serial port communication so I'd like the programming to be as simple as possible.  How do I open the port, get the data, convert it to a string, and write that string to an existing array, all in an existing while loop?   Help on this would be greatly appreciated. 

as far as I can tell no driver currently exists for this particulat model of Scale (Mettler-Toledo JL-G Jewelry Balance)

Attached is the existing VI. I'd like the weight data to appear as the last column in an output file with the same timing as the other data points, though less frequent collection of weight data is acceptable (but not ideal).

Grateful novice,

Jo