Serial port termination character status?

Hello,
I need to read a message from a serial port and I'm having some problems. I used the advanced serial communication example and came up with the attached program. Everything works perfectly fine except for the fact that if no message is sent for 10 seconds as designed the serial read outputs an error. I know normally I can check to make sure there are bytes at the port before I do a read operation which solves this problem. However, when using the buffer to terminate the read once a termination character is provided the bytes at port property always returns 0 so I can't use this as a conditional for reading the port.
Is there a way to prevent the serial read from timing out in the attached program? Thank you.
Attachments:
serial_buffer.gif ‏19 KB
serial.vi ‏15 KB

Let me maybe give a bit more details about the application. I want to be able to get any amount of characters as a string that someone inputs in to the serial port. This will be a computer so I can expect the commands to usually be valid but I want to provide some additional redundency incase a person at a terminal is writing commands. The commands might be "measure 110" or it might be "set 23 34". So the amount of bytes being sent will depend on the command. I used 1000 as the byte count on the read just to provide as much room as possible, setting it to 100 doesn't really make a difference in this application, the same thing happens. If someone starts typing in a terminal "measure 110" (for example) but forgets to hit enter for the termination character the program will time out since the error cluster is connected to the stop button of the loop. When this happens the entire program needs to be restarted. Not really ideal.
If I disconnect the error cluster from the stop button I noticed it works perfectly fine. After 10 seconds of the terminator character not being entered the buffer clears and the loop simply restarts. What I worry about is if there is some other fatal error (such as not being able to connect to the serial device) that the program will keep running. Is this something I even need to worry about?
Attached is a screenshot of my latest program which works great but like I said I'm just worried about not wiring the status from the error cluster to the stop button since that seems to be what I've always been taught to do. If I wire the byte count to the number of bytes property it will only collect the number of bytes I set, since this will vary based on the command that won't really work in this application.
Attachments:
serial_buffer.gif ‏20 KB

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> Hi there,
>
> (LabView 6.02 on Win2k)
> Trying to communicate with a serial device I open a VISA-session on COM1
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>
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>
>
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>

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Private Sub txtMessage_KeyPress(KeyAscii As Integer)
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Attachments:
Getaxisno test.vi ‏18 KB

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billko wrote:
Ranjeet_Singh wrote:
I need to read data from two COM port and order of data appearance from COM port is not fixed.
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I need my difficulties because they are necessary to enjoy my success.
--Ranjeet

Serial port termination character status?

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