How to send byte data to serial port

[TestEngineer11]

Hello,

I am trying to communicate with a non-commercial device that uses RS-232 for communication. I'm using the "simple serial" example vi approach. I know all the correct settings I need ( baud rate, stop bits, parity etc...) so I know that won't be an issue. The question I have is more around implementing what I want to send in the correct format in LabVIEW.

My understanding is that VISA expects the message to be supplied as a string type. I was going to simply use the byte-array-to string approach but the problem is that some of the data I will be sending will be numbers that aren't representable in one byte. For example the data I'm trying to send may look like this:

MESSAGE HEADER: (decimal)

msg[0] = 1

msg[1] = 63

msg[2] = 0

msg[3] = 6300

DATA PORTION (decimal):

msg[4] = 'C'

msg[5] = '!'

msg[6] = 76509

......

How can I work with values as integers so that I can peform arithmetic operations on them, but still have them be stores as U8 byte types for my string input to visa? Should I just forget that function and instead type cast everything as a string value?

Thanks!

[crossrulz · Accepted solution]

Personally, I am a big fan of Flatten Into String and its opposite Unflatten From String.  Those functions can handle any data type and just flattens the raw data into a string data type.

[TestEngineer11]

Thanks for feedback. So if I have an array of integers and I pass them through the "flatten to string" function, will VISA correctly transmit that to the serial port? Because when I look at the output it looks like garbage. See attached example.

[crossrulz]

Setting the proper display style(s) helps.  For the numerics, right click and choose Visible Items->Radix.  There will be a little icon show up in the control/indicator showing which radix (display format) is being used.  You can click on that icon and choose a different format.  I used "Hex".  Similarly, you can right-click on the string and choose Visible Items->Display Style and then choose the hex format.

Also note that I wired up a FALSE constant to the "Prepend Array or String Size" so that the size is not added to the beginning of the string data.