Help needed setting up an accelerometer via serial port

Hoping you might be able to give me some advice and point me in the right direction as my experience with labview is limited.
I am wanting to read data from an accelerometer streaming through a serial port. Using the labview examples i have no problems in connecting to the device and seeing the data but i am going around in circles trying to work out where to from now.
I need to create a VI which would show data streaming and then gives the user the ability to save data for various time periods to a text file. I am getting stuck as the data from the accelerometer is constantly streaming in 20byte packets every 2ms in the following format: 7E 00 0E 83 00 00 26 00 01 0E 00 02 00 01 F9 02 64 E5, where 00 02 01 F9 02 64 is the data of interest and of course when starting to read from the device it isnt necessary going to begin at the start of the packet.
I am assuming that inside the while loop i need to get the vi to scan the string to find the start of the first packet and then begin writing it to an array using a shift register for each sample with the left over from the string if not reading the full packet being attached to the next read, then if the data is to be saved to a txt file get it to enter a for loop for the user to define the number of samples to be saved or use an index array option to save a subset of data to a txt file.
Would greatly appreciate any device or examples of the most efficient way to set this up before i lose my sanity!

The easy way is a three step process.
First, acquire 2n-1 bytes (39 in your case) so you are sure you have a full set of data. Parse out the first full set using the string utilities (match pattern, split string, etc.). The remainder of the string is the start of your next data set.
Second, acquire enough points to get the next data set and parse it.
Third, continue looping and getting 20 bytes (keep verifying your start and end so you know if there are glitches).
A harder, but far more robust, way, is the following:
Read in data until you get your start sequence. A circular buffer would be useful for this (you will need to implement this yourself).
Read in your data of interest and record/save/...
Read in the terminator.
Repeat as needed.
For all of these, you can use a flat sequence in a loop, but a state machine is far easier and more flexible in the long run. Check out the LabVIEW help and these forums for how to create and use a state machine.
It is often easier to use arrays of U8s instead of strings for this type of data manipulation. Under the hood, they are the same thing, so the conversions between the two are highly efficient.
Let us know about any problems you run into.
This account is no longer active. Contact ShadesOfGray for current posts and information.

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How to transfer file from PC to PC via serial port using labview

I need to transfer files(.txt, .doc, .xls) from PC to PC via serial port using LabVIEW. Is it possible to transfer files, if so how to transfer?
Solved!
Go to Solution.

Yes, it is possible to transfer files with the serial port using LabVIEW. Files are just collections of bytes and the serial port is pretty good at shipping bytes from one PC to another. You need to connect the serial ports together with a null modem cable.
First, take a look at the example for serial communication. In LabVIEW, go to the Help menu and select "Find Examples...". From there you can search for "serial" or navigate to Hardware Input and Output >> Serial. Select the "Basic Serial Write and Read.vi". Experiment with that example to gain confidence on the serial communication methods.
Next, it's time to learn about how to read and write files. For that, the examples could be somewhat confusing since they all deal with files that are presumed to have data of a specific type in them. I would recommend just getting familiar with the functions on the File I/O palette. Specifically, get to know the following functions.
Open/Create/Replace File - On your destination side, you'll need to create the copy of the file that you are trying to transfer
Close File - When you are finished reading from or writing to a file, you should close it. It cleans up the memory being used and finalizes any write operations that are still floating in the write buffer.
Read From Binary File - The best way to read from a file when you do not really care what type of file it is. In your case, you just want to get those bytes read and sent out so they can be written down at the destination.
Write to Binary File - At the destination side, this is what will store those bytes to the file you created with number 1.
Get File Size (under the Advanced File Functions sub-palette) - You need to know how big the file is so you know when you are finished.
OK, so once you are able to create files, write bytes to them, and read bytes from existing files you can move on to transferring.
The basic method I would suggest is to have the user specify a source file on the source PC and a destination folder on the destination PC. Then, find out the size of the source file using number 5. Divide that size number by the number of bytes you feel like transferring at once. The serial buffers are usually around 32k (if I remember correctly) so do not exceed that. Now begin sending data by reading some number of bytes and wiring that string output to the VISA Write function. On the destination side, you'll want to be monitoring the serial port for bytes and reading them when they arrive. Wire that string to the Write to Binary File function to add them to your destination file.
That is the basic outline of how to do it. You have to be careful not to overload the write and read buffers on the serial ports. Initially you can use delays on the sending side to make sure the reading side has enough time to digest. To get things moving faster, you can bring in some flow control.
If all that sounds a bit intimidating, there are Alliance Member companies out there (such as PrimeTest Automation) who can write such code for you and even provide a turnkey solution for you.
Happy wiring,
Dan Press
Certified LabVIEW Architect
PrimeTest Automation

How can i browse FP 2000 via serial port same use Ethernet port(RJ 45)?

I am a new user for labview.I develope my program with FP 2000 but I have some problem
1 How can i browse FP 2000 via serial port same use Ethernet port(RJ 45)? if it can Tell me please.
  2 If I use GSM/GPRS modem via FP 2000 rs 232 port (I under stand how to send AT command) and leave it stand alone
     Can I dial modem and browse file in FP 2000 same as use Ethernetport?
Someone please help me.Thank you very much.

Hi!
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      3) In your application, you should build a kind of serial port manager, and by the means of serial port you send/receive commands from PC.
    The commands from PC can include "Tell me the about the FP 2000 file system ", or "switch on line X", or anything you need.
   I think it would be difficult to use Internet exp, because you use IE with TCP/IP, and TCP/IP is over ethernet.
   I know that for Windows you can find some wrappers that make you "see" the serial port as an ethernet, but these wrapper do not exist under filed Point, and you shoul build one yourself!!!(and that's not easy).
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   So, what I say, is just build, for now, a simple embedded application for FP2000, that, using RS232, sends data to a PC (you should see data sent with use of Hyper terminal).
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Problem communicating via serial port in Linux

Hello,
I am trying to transfer data via serial port, in Linux.
But it is impossible till now!
I get Runtime exception.
Here is my code:
public class Main {
    public Main() {
    int num=5;
    int[] array = new int[5];
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                array[0]=1;
                array[1]=2;
                array[2]=3;
                array[3]=4;
                array[4]=5;
                new ParallelCommunication(num,array);
import java.io.*;
import java.util.*;
import javax.comm.*; // for SUN's serial/parallel port libraries
//import gnu.io.*; // for rxtxSerial library
public class ParallelCommunication implements Runnable, SerialPortEventListener {
   static CommPortIdentifier portId;
   static CommPortIdentifier saveportId;
   static Enumeration portList;
   InputStream inputStream;
   SerialPort serialPort;
   Thread readThread;
   static OutputStream outputStream;
   static boolean outputBufferEmptyFlag = false;
   int num;
   int[] array;
   public ParallelCommunication(int this_num,int[] this_array) {
      boolean portFound = false;
      String defaultPort;
      num = this_num;
     array=new int[this_array.length];
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      String osname = System.getProperty("os.name","").toLowerCase();
      if ( osname.startsWith("windows") ) {
         // windows
         defaultPort = "COM1";
      } else if (osname.startsWith("linux")) {
         // linux
        defaultPort = "/dev/ttyS0";
      } else {
         System.out.println("Sorry, your operating system is not supported");
         return;
//      if (args.length > 0) {
//         defaultPort = args[0];
      System.out.println("Set default port to "+defaultPort);
      // parse ports and if the default port is found, initialized the reader
      portList = CommPortIdentifier.getPortIdentifiers();
      while (portList.hasMoreElements()) {
         portId = (CommPortIdentifier) portList.nextElement();
         if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
            if (portId.getName().equals(defaultPort)) {
               System.out.println("Found port: "+defaultPort);
               portFound = true;
               // init reader thread
               initialize();
               break;
      if (!portFound) {
         System.out.println("port " + defaultPort + " not found.");
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      // initwritetoport() assumes that the port has already been opened and
      //    initialized by "public void initialize()"
      try {
         // get the outputstream
         outputStream = serialPort.getOutputStream();
      } catch (IOException e) {}
      try {
         // activate the OUTPUT_BUFFER_EMPTY notifier
         serialPort.notifyOnOutputEmpty(true);
      } catch (Exception e) {
         System.out.println("Error setting event notification");
         System.out.println(e.toString());
         System.exit(-1);
   public void writetoport(int counter) {
      try {
         // write string to serial port
         outputStream.write(String.valueOf(array[counter]).getBytes());
      } catch (IOException e) {}
   public void initialize() {
      // initalize serial port
      try {
         serialPort = (SerialPort) portId.open("SimpleReadApp", 2000);
      } catch (PortInUseException e) {System.out.println("Port In Use.");} //******Here is the Exception******
      try {
         inputStream = serialPort.getInputStream();
      } catch (IOException e) {}
      try {
         serialPort.addEventListener(this);
      } catch (TooManyListenersException e) {}
      // activate the DATA_AVAILABLE notifier
      serialPort.notifyOnDataAvailable(true);
      try {
         // set port parameters
         serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8,
                     SerialPort.STOPBITS_1,
                     SerialPort.PARITY_NONE);
      } catch (UnsupportedCommOperationException e) {}
      // start the read thread
      readThread = new Thread(this);
      readThread.start();
   public void run() {
      // first thing in the thread, we initialize the write operation
     initwritetoport();
     for(int i=0; i<=num_of_inputs; i++) {
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     serialPort.close();
   public void serialEvent(SerialPortEvent event) {
      switch (event.getEventType()) {
      case SerialPortEvent.BI:
      case SerialPortEvent.OE:
      case SerialPortEvent.FE:
      case SerialPortEvent.PE:
      case SerialPortEvent.CD:
      case SerialPortEvent.CTS:
      case SerialPortEvent.DSR:
      case SerialPortEvent.RI:
      case SerialPortEvent.OUTPUT_BUFFER_EMPTY:
         break;
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         byte[] readBuffer = new byte[20];
         try {
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            while (inputStream.available() > 0) {
               int numBytes = inputStream.read(readBuffer);
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         break;
}...and the outcome is :
Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException:
Error opening "/dev/ttyS0"
tcgetattr(): Input/output error
at com.sun.comm.LinuxDriver.getCommPort(LinuxDriver.java:66)
at javax.comm.CommPortIdentifier.open(CommPortIdentifier.java:369)
at ParallelCommunication.initialize(ParallelCommunication.java:128)
I have searched a lot and I couldn't find a solution.
Thank you.

I'm having the same problem this helped somewhat debug the problem
http://bloggerdigest.blogspot.com/2006/11/linux-serial-com-port-diagnostic-test.html
I'm running Suse 10.3 and apparently it does not recognize my serial ports. So before
you can test your Java code you have to figure out how to make linux see the ports.
If I find a solution I'll let you know but if you find one first let me know. Thanks.

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Hi Francesc,
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Thanks for the reply
I can get it sending bytes of info from one machine to
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On CUCM no, but with CME it can be done (by collecting syslog output). Otherwise you may exploit the CDRs on the voice gateway.
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tajava
Welcome to the forum. Please refrain from posting in old threads that are long dead. When you have a question, please start a topic of your own. Feel free to provide a link to an old thread if relevant.
I also suggest you go through these links before posting again:
[How to ask questions the smart way|http://catb.org/~esr/faqs/smart-questions.html]
[How To Get Good Answers To Your Questions|http://www.tek-tips.com/viewthread.cfm?qid=473997]
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db

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CC
Chilly Charly (aka CC)
E-List Master - Kudos glutton - Press the yellow button on the left...

Help needed setting up print server

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I didn't say it's impossible. I just offered an easy solution to your problem that will save you and you users some hassle in the long run (eg. when you come to troubleshoot you wn;t have to look at 2 networks and a firewall). I guess I just like easy solutions. And ,dude, 20 bucks...
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Help Needed Setting Up IMAP Relay?

I an currently maintaining an OS X 10.4.11 Tiger server, running on a PowerMac G4 Mirror.
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Gambin,
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free to modify this vi and use it as you see fit. I have left
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Roy
Attachments:
HextoCommand.vi ‏17 KB

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I have previously developed an automated video microscope application in Labview. It worked great. My setup was: NI PXI system with 1409 image board, 7344 motion controller, 7764 breakout box, stepper motors, motor drivers, and tables. Now, a customer is requiring that we use a specific brand of drivers that encompass a motion controller and are daisy-chained together. Communication will take place from a serial port, thereby bypassing the 7344. My question is: will I have to can my entire previous Labview motion/data acquisition program b/c I won't be using the 7344 controller? Or, will it be easy to specify in the program to commmunicate via the serial port rather than the card? Would this setup take place in MAX, or in the LabView applicatio
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NI-Germany

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Hi
Is it possible to communicate between the client serial port and an Apex application?
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