Is there a 400ms serial comm timeout function in VI?

[BC@Baxter]

Hello,

I am a new Labview user.  I have an instrument that would continuously send out 20 bytes of data every 500ms at the 9600baud/8data/1parity rate connected to COM5(via USB) port of a NI PXI box. I want to extract & display the 8th byte from every transmission continuously. Which VI function can I use to wait for the 400ms communication timeout first before starting the VISA RD and then Parse function?  If I don't use timeout to begin READ, I am worried that it would start counting the bytes at the wrong place and get out of sync.  Any suggestion would be greatly appreciated.

BC@Baxter

[Wayne.C]

You need to sync up with the data stream before starting a loop that continuously reads the buffer every 500mS.  Does the 20bytes of data end with a unique termination character?  If so you can use VISA events to detect when the termination character has been received.  You could then dump the buffer and start a loop that read 20 bytes of data from the buffer every 500ms.

You could also use the VISA Events to detect the absence of incoming data for a period greater that say 100mS.  Once you detect the gap between data transmissions, dump the buffer and start your loop.