All: My apoligies for what may be a simple question. (Newbie, LV 8.2) I am controlling a series of 8 Mass Flow Controllers via rs-232 and there are no drivers or VI's for this machine (Environics series 2000) available. I was able to decrypt the codes I need to send through the VI, and the Basic Write/Read VI works well. The actual command set I will be using is as follows: (ctrl B) ^B FLOW X, TARGET = Y ^C. In this case, X will be hard coded in the string as the mass flow controller number(1,2,3..8), but I need the user to input Y (flow in SCCM). This sequence will be added to a bunch of other VISA Read functions that I have working, and set into a loop that are just feedback from the machine. Once this process starts, I will need to grab this number, I think using a write from a string, change to a number, and associate it with a control loop, whereby the 4-20 mA output of an analyzer will add and subract from the mass flow controller value as an automatic adjustment to the output. This value will then get written back into the string, and the loop starts again until it times out or the user hits stop. The issue I cannot resolve: How can I construct a box on the Front Panel where the user inputs a number (1.0 to 30,000.0), and this value gets injected into the command string that is on the front end of a VISA Write box? ALso, how can I construct a similar box where the "automatically adjusted" value gets written back into the VISA Write? Any and all help would be much appreciated. Been banging my head on this for much of the past 3 days. I am looking forward to the next available class. Thanks; Zig.

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LabVIEW

ETX is ascii character 03 (in hex). STX is 02. They show up in that string constant which has been set for hex display.

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Thanks everyone for the help and quick responses! I figured it out

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Hi. I am also about to embark on using the Environics 2000 with Labview. Are there any tricks, tips or source code that you could share with me?

Thank you

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