Digital line input from a Jennic zigbee kit to data acquisition BNC 2432
I am working on a project involving data acquisiton of data from a Jennic zigbee microcontroller . I am getting burst of data form a line of the kit which tells about the temperature and light signal. How do i give as an input to labview. I tried with the normal data acquisiton it always shows a hight and i dont see any transition. When i try t sample in different frequency i am not able to do it. i get an error.. How do i get the data out in the form of 8 bit codes so i can represent in the corresponding temp-erature./ light intensity///
Hi saty,
Thank you for posting to the NI forums. Which data acquisition (DAQ) device are you using – or are you using serial communications? The 2432 is not (at least currently) made by NI, but Tektronix has a product with that model number – is this what you’re using? Also, what is the error that you are receiving?
If you are using a DAQ device, are you using the Traditional DAQ drivers or DAQmx. There are numerous examples for each in the LabVIEW Example Finder. Browse to Hardware Input and Output and then select your driver. There will be digital I/O examples for both driver versions.
Please post back, and with more information, I can give you some better recommendations for the architecture of your program.
Ed W.
Applications Engineer
National Instruments
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Problem with tokenized input from command line
I am trying to take an input from the command line, parse it to tokens and perform whatever operation is needed depending on the name of the token, on a binary tree of stacks for example, if i type 1 2 1 3 printLevelOrder, then the root of the tree should have 3, 2,1 in the stack, the left child should have 1 and the right child should be empty. and then a level order print of the tree should be performed.
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example input and output shown below code fragment.
try {
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String line = "";
while (line != "***") {
System.out.print("> prompt ");
line = in.readLine();
StringTokenizer tokenizer = new StringTokenizer(line," ");
String word = new String();
while (tokenizer.hasMoreTokens()) {
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if (word =="printLevelOrder") {
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notCommand=false;
if (word == "printPopPreorder") {
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notCommand=false;
if (word == "printPopRoot") {
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notCommand=false;
if (word == "***") {
notCommand=false;
if (notCommand == true) {
System.out.println("(notCommand == true)");
boolean notPlaced = true;
int v = 1;
while ((notPlaced==true) && (v < theTree.size())) {
if (theTree.element(v).isEmpty()) {
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notPlaced=false;
if (notPlaced==true) {
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notPlaced=false;
v++;
}valid inputs: int value, printLevelOrder, printPopLevelOrder, printPopInorder, p
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Inserting1
in empty stack at location: 1
(notCommand == true)
Inserting3
in stack at location: 1
(notCommand == true)
Inserting2
in empty stack at location: 2
(notCommand == true)
Inserting4
in stack at location: 1
(notCommand == true)
Inserting2
in stack at location: 2
(notCommand == true)
Exception in thread "main" java.lang.NumberFormatException: For input string: "printLevelOrder"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
at java.lang.Integer.parseInt(Integer.java:447)
at java.lang.Integer.valueOf(Integer.java:553)
at TreeStack.main(TreeStack.java:73)
Press any key to continue . . .lol aww, shame that you forgot to do that. i had 10 / 10 for mine, and seing as the deadline is now well and trully over,
here is the entire source for anybody who was following the discussion or whatever and wanted to experiment.
additional files needed >
http://users.cs.cf.ac.uk/Paul.Rosin/CM0212/Stack.java
http://users.cs.cf.ac.uk/Paul.Rosin/CM0212/ArrayStack.java
http://users.cs.cf.ac.uk/Paul.Rosin/CM0212/StackEmptyException.java
http://users.cs.cf.ac.uk/Paul.Rosin/CM0212/StackFullException.java
/*TreeStack.java - reads command line input of values and assigns them to stacks in a binary tree and performs
operations on the ADT. valid inputs: <int>, printLevelOrder, printPopLevelOrder,
printPopInorder, printPopPreOrder, printPopRoot. Terminates on invalid input.
Written by George St. Clair.
S/N:0208456 22/11/2005
import java.util.Vector;
import java.io.*;
import java.util.StringTokenizer;
public class TreeStack {
private final int TREE_CAPACITY = 7 + 1;
private final int STACK_CAPACITY = 10;
Vector tree = new Vector(TREE_CAPACITY) ;
//collect input from command line, add values to stacks at nodes of the teee
//and perform required operations on the treestack
public static void main (String [] args) {
//create a tree of stacks
TreeStack theTree = new TreeStack ();
try {
//collect standard input
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String line = "";
while (line != null) {
System.out.print("");
line = in.readLine();
//tokenise input
StringTokenizer tokenizer = new StringTokenizer(line," ");
String word = new String();
while (tokenizer.hasMoreTokens()) {
//assign word to the token
word = tokenizer.nextToken();
boolean notCommand = true;
//perform operation on treestack depending on what word is
if (word.equals("printLevelOrder")) {
System.out.println("printLevelOrder");
theTree.printLevelOrder();
notCommand=false;
if (word.equals("printPopLevelOrder")) {
System.out.println("printPopLevelOrder");
theTree.printPopLevelOrder();
notCommand=false;
if (word.equals("printPopInorder")) {
System.out.println("printPopInorder");
theTree.printPopInorder();
notCommand=false;
if (word.equals("printPopPreorder")) {
System.out.println("printPopPreorder");
theTree.printPopPreorder();
notCommand=false;
if (word.equals("printPopRoot")) {
System.out.println("printPopRoot");
theTree.printPopRoot();
notCommand=false;
//if word was not a command it must be a number
if (notCommand == true) {
boolean notPlaced = true;
int v = 1;
//starting at the root, find suitable place for number
while ((notPlaced==true) && (v < theTree.size())) {
//if the stack at v is empty, number goes here
if (theTree.element(v).isEmpty()) {
theTree.element(v).push(Integer.valueOf(word));
System.out.println("inserting: "+word);
System.out.println("in empty stack at location: "+(v-1));
notPlaced=false;
//if the stack is not empty
if (notPlaced==true) {
//if the value on the top of the stack is smaller than number, number goes onto the stack
if ( Integer.valueOf(word) > Integer.valueOf( theTree.element(v).top().toString() ) ) {
theTree.element(v).push(Integer.valueOf(word));
System.out.println("inserting: "+word);
System.out.println("in stack at location: "+(v-1));
notPlaced=false;
//if that node was no good, check the next one for suitability
v++;
catch (Exception e) {
//occurs when user inputs something that is neither a command, or a number, or upon EOF, or stack is full
public TreeStack () {
//create the TreeStack ADT by adding stacks in the vector, note vector 0 is instantiated but not used.
for (int i = 1;i<=TREE_CAPACITY;i++)
tree.add(new ArrayStack(STACK_CAPACITY));
public int size() {
//return the size of the tree +1 (as 0 is not used)
return tree.size();
public ArrayStack element (int v) {
//return the ArrayStack at v
return (ArrayStack)tree.get(v);
public int leftChild (int v ) {
//return left child of v
return v*2;
public int rightChild (int v ) {
//return the right child of v
return v*2+1;
public boolean children (int v ) {
//search for children of v and return true if one exists
for (int i =v;i<size();i++) {
if (i/2==v ) {
//left child found at i
return true;
if ((i-1)/2==v ) {
//right child found at i
return true;
//no children found
return false;
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//test whether node v is internal (has children)
if (children (v)== true) {
//has children
return true;
return false;
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//for every node of tree v
for (int v = 1;v<size();v++) {
if (!element(v).isEmpty() ) {
//print the top value in stack v
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else {
//stack at v is empty
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//for each node of tree v
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System.out.println(" "+element(v).top());
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element(v).pop();
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System.out.println(" -");
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printPopInorder (1);
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System.out.println(" -");
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Attachments:
sensor.vi 34 KBHello Parky,
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The application has two main components: The form and a class. The form takes care of interpreting the commands that the user enters and the class implements the three batch commands (more to follow in the near future). The issue that I am having is that
sometimes (maybe 2%) the INPUT functionality does not work. When I enter a string and press Enter an empty string is returned. I have tried to debug this as much as I can, but it is difficult since this problem only happens once in a while.
I have extracted the INPUT functionality and duplicated it in a simple app which I present here. The test app contains one button called btnConRead and a multi line text box called txtConsole. Clicking the button "forces" the app into "run"
mode where the batch commands are interpreted. For this example I run the code that runs when an INPUT command is being processed. The app prompts with "OK" and waits for the user to type something in. When the user presses the Enter key the entered
string is echoed on the console. The form module contains this code:
string sKBBuf = ""; //App wide KB buffer when form Key preview is enabled.
bool bEnter;
private delegate void DisplayMsgDelegate(string sMsg);
private void cEventPrint(object sender, PrintDataEventArgs e)
Display(txtConsole, e.sPrintLine);
private void cEventRead(object sender, ReadDataEventArgs e)
//Event that reads text from the console and returns it.
//This event requires input from the user. It traps the program here until the user
//presses Enter.
//Clear the KB buffer.
sKBBuf = "";
//Loop incessantly until user presses Enter key or Stop key (s).
do
//Braindead.
} while (!bEnter);
if (bEnter)
//User pressed the Enter key, return the KB buffer.
e.sReadLine = sKBBuf;
//Empty buffer.
sKBBuf = "";
//Reset Enter key flag.
bEnter = false;
//Push CRLF to console.
Display(txtConsole, Environment.NewLine);
private void DisplayMsg(string sMsg)
txtConsole.AppendText(sMsg);
private void Display(TextBox txtOutput, string sMsg, bool bToCon = true)
//Check output to console flag.
if (bToCon)
if (txtOutput.InvokeRequired)
txtOutput.Invoke(new DisplayMsgDelegate(DisplayMsg), sMsg);
else
txtOutput.AppendText(sMsg);
private void GetConInput()
clsExample cEx = new clsExample();
cEx.ReadData += cEventRead;
cEx.PrintData += cEventPrint;
System.Threading.Thread runThread = new System.Threading.Thread(() =>
cEx.Process();
this.KeyPreview = false;
this.KeyPreview = true;
runThread.Start();
private void btnReadCon_Click(object sender, EventArgs e)
//Prep stuff
sKBBuf = "";
txtConsole.Focus();
Display(txtConsole, "OK" + Environment.NewLine);
//Read console textbox
GetConInput();
private void Form1_KeyPress(object sender, KeyPressEventArgs e)
bEnter = e.KeyChar == 13;
//Save to buffer. At this time I am not distinguishing from letter or digits.
//But I do need to check for a BS.
if (e.KeyChar == 8)
//Yeah, BS, remove the last char, if any.
if (sKBBuf.Length > 0)
sKBBuf = sKBBuf.Substring(0, sKBBuf.Length - 1);
else
sKBBuf += e.KeyChar;
The class is called clsExample and contains the following code:
//Event raised when data needs to be printed to console.
public event EventHandler<PrintDataEventArgs> PrintData;
//Event raised when data needs to be read from console.
public event EventHandler<ReadDataEventArgs> ReadData;
protected virtual void OnReadData(ReadDataEventArgs e)
EventHandler<ReadDataEventArgs> handler = ReadData;
if (handler != null)
handler(this, e);
protected virtual void OnPrintData(PrintDataEventArgs e)
EventHandler<PrintDataEventArgs> handler = PrintData;
if (handler != null)
handler(this, e);
public void Process()
ReadDataEventArgs argsRead = new ReadDataEventArgs();
PrintDataEventArgs args = new PrintDataEventArgs();
string sMsg = "";
//Get input from user.
OnReadData(argsRead);
if (argsRead.sReadLine.Length > 0)
//I have something
sMsg = argsRead.sReadLine;
else
//No data
sMsg = "*";
args.sPrintLine = sMsg + Environment.NewLine;
OnPrintData(args);
Plus two more support classes for the Print and Read events:
public class PrintDataEventArgs : EventArgs
public string sPrintLine { get; set; }
public class ReadDataEventArgs : EventArgs
public string sReadLine { get; set; }
All the above was necessary so that the Process procedure running in a different thread could interact with the UI elements in the main form. The above mostly works, but I wonder if I am doing it the right way. I don't particularly like the use of
global flags, such as bEnter or having empty loops to just "kill" time, such as the one found in the cEventRead procedure.
In the cEventRead procedure I had the if() block immediately following the empty loop inside
the loop and moved it out of there to see if this made any difference, but apparently it did not. Can anyone provide any feedback or suggestions of what I could change to make it work 100% of the time? I appreciate your time and effort. Thank you, Saga
You can't take the sky from meHi all. I am learning C# and have a Windows forms project that I am working on to learn various techniques. Basically it has a text box that I use to mimic a console. The user enters a command followed by the Enter key and the program reads that in and interprets
it. I also have some rudimentary "batch" commands, such as IF/THEN, INPUT and PRINT.
//Loop incessantly until user presses Enter key or Stop key (s).
do
//Braindead.
} while (!bEnter);
Hi Saga,
Please don't use such kind of loop in your code, if you want to monitor the user input, just use the KeyPress event provided by the TextBox control.
Control.KeyPress
Event
If you just want to execute some standard commands, I recommend that you use
Process to start cmd.exe to execute the command, for example:
void ExecuteCommand(string command)
int exitCode;
ProcessStartInfo processInfo;
Process process;
processInfo = new ProcessStartInfo("cmd.exe", "/c " + command);
processInfo.CreateNoWindow = true;
processInfo.UseShellExecute = false;
// *** Redirect the output ***
processInfo.RedirectStandardError = true;
processInfo.RedirectStandardOutput = true;
process = Process.Start(processInfo);
process.WaitForExit();
// *** Read the streams ***
string output = process.StandardOutput.ReadToEnd();
string error = process.StandardError.ReadToEnd();
exitCode = process.ExitCode;
Console.WriteLine("output>>" + (String.IsNullOrEmpty(output) ? "(none)" : output));
Console.WriteLine("error>>" + (String.IsNullOrEmpty(error) ? "(none)" : error));
Console.WriteLine("ExitCode: " + exitCode.ToString(), "ExecuteCommand");
process.Close();
If it's powershell script, you can also use the existing library to execute it, check this blogpost:
Executing PowerShell scripts from C#
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