Multiple serial port initialisation problem

Good Morning All
I have attached a vi which is giving me a problem that I can't solve, and would appreciate any help.
The vi is supposed to intialise up to 7 serial ports (only using 5 at the moment), and I'm assuming this is a plausible way to do the initialisation (could be wrong). The serial ports are connected to a pc via a usb hub. The windows XP o/s does recognise the ports according to the device manager.
The problem is that when the vi is run the following error is reported as shown in the attached word document.
I have compared the port settings in the device manager properties for each port to the vi settings and they match. What more can I do?
If somebody has a setup with mutliple serial ports could they try the vi and see if it works for them?
Thanks and best regards
Ray
Solved!
Go to Solution.
Attachments:
ax500 serial port init.vi ‏37 KB
init error.docx ‏518 KB

It has nothing to do with multiple serial ports. It has to do with an invalid setting you are trying to use to configure any one of the serial ports.
Look at the information in the error message. Argument 4 of the property node in Configure Serial Port VI is the Stop Bits setting. I see a coercion dot going into that VI, so that tells me the datatype you are wiring in doesn't quite match.
You have an array of I32 values, and your values consist of 1's. Disconnect that array and right click on the terminal of Configure Serial Port VI and pick Create Constant. You'll see you get a ring data type. It is a U16. But if you look at the items in there, you'll see that stop bits 1.0 has a value of 10. 1.5 has a value of 15, 2.0 has a value of 20. So the value of 1 has no meaning to that property node and you get an error. You should be wiring in a value of 10.
Delete that array. Create an array of the ring constants. Turn it into a control, and choose the correct ring value for each element of your array.
You have several other coercion dots. They may not be causing you problems, but I would consider disconnecting them, creating a constant of the correct datatype, and using that in the array you wire to the Configure subVI.
I modified your VI and attached it. See if it works for you.
Attachments:
ax500SerialPortInitMOD.vi ‏37 KB

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Attachments:
Serial Port Error.jpg ‏63 KB

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Hi Friend,
I reading the serial port one character at a time , i specified it in the "serial bytes to read" option in serial port read examples.
The problem is ----------i can able to read the data.
but only the first character is reading again and again...and "reading string indicator" in the serial port example shows only the first character sent ..only for a single time.since i am reading continously ----aleast the first character should display as many times i running the program
(i am running the vi by run continous option..........)..
please help me ....how to read the character one by one.....
regards
rajasekar

Hi jason...
I can able to read the serial port by 1 byte or 2 byte or 4 byte as i can specify it in the serial port read bytes option..(in visa serial read)..
I need to acquire 4 bytes of data and pass it to the Math-script node..and save these 4bytes of data in array (1 row and 4 column)..
And split this array(just like array-indexing.vi) and processing it each each column separately....
or suggest some method to achieve my task.....please.
one more thing the math-script node is placed in a while loop.....in order to read sequence of bytes continously.......
regards
rajasekar

Multiple serial port initialisation problem

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