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  • How to have an Arduino wait until it receives data over serial?

    - by SonicDH
    So I've wired up a little robot with a sound shield and some sensors. I'm trying to write a sketch that will let check the sensors. What I'd like for it to do is print out a little menu over serial, wait until the user sends a selection, jump to the function that matches their selection, then (once the function is done) jump back and print the menu again. Here's what I've written, but I'm not a that good of a coder, so it doesn't work. Where am I going wrong? #include <Servo.h> Servo steering; Servo throttle; int pos = 0; int val = 0; void setup(){   Serial.begin(9600);   throttle.write(90);   steering.write(90);   pinMode(A0, INPUT);   pinMode(7, INPUT);   char ch = 0; } void loop(){   Serial.println("Menu");   Serial.println("--------------------");   Serial.println("1. Motion Readout");   Serial.println("2. Distance Readout");   Serial.println("3. SD Directory Listing");   Serial.println("4. Sound Test");   Serial.println("5. Car Test");   Serial.println("--------------------");   Serial.println("Type the number and press enter");   while(char ch = 0){   ch = Serial.read();}   char ch;   switch(ch)   {     case '1':     motion();   }    ch = 0; } //menu over, lets get to work. void motion(){   Serial.println("Haha, it works!"); } I'm pretty sure a While loop is the right thing to do, but I'm probably implementing it wrong. Can anyone shed some light on this?

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  • What are typical server to client communication patterns?

    - by jagse
    What are the usual patterns for bidirectional communication between a client and a server in a wlan environment. How is it possible for the server to push data to a mobile client over wlan after a connection has been established. Lets say I have a webservice running on a server and the moblie cients in the wlan can use this webservice. Now the question is how can the server invoke methods at the client, or directly send data to the client. How is this handled usually? I would apriciate some links to read about this topic. Is this a common problem or is it not that easy to solve? Cheers

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  • Implementation communication protocols in C/C++

    - by MeThinks
    I am in the process of starting to implement some proprietary communication protocol stack in software but not sure where to start. It is the kind of work I have not done before and I am looking for help in terms of resources for best/recommended approaches. I will be using c/c++ and I am free to use use libraries (BSD/BOOST/Apache) but no GPL. I have used C++ extensively so using the features of C++ is not a problem. The protocol stack has three layers and it is already fully specified and formally verified. So all I need to do is implemented and test it fully in the specified languages. Should also mention that protocol is very simple but can run on different devices over a reliable physical transport layer Any help with references/recommendations will be appreciated. I am willing to use a different language if only to help me understand how to implement them but I will have to eventually resort to the language of choice.

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  • Fake serial communication under Linux

    - by kigurai
    I have an application where I want to simulate the connection between a device and a "modem". The device will be connected to a serial port and will talk to the software modem through that. For testing purposes I want to be able to use a mock software device to test send and receive data. Example Python code device = Device() modem = Modem() device.connect(modem) device.write("Hello") modem_reply = device.read() Now, in my final app I will just pass /dev/ttyS1 or COM1 or whatever for the application to use. But how can I do this in software? I am running Linux and application is written in Python. I have tried making a FIFO (mkfifo ~/my_fifo) and that does work, but then I'll need one FIFO for writing and one for reading. What I want is to open ~/my_fake_serial_port and read and write to that. I have also lpayed with the ptymodule, but can't get that to work either. I can get a master and slave file descriptor from pty.openpty() but trying to read or write to them only causes IOError Bad File Descriptor error message.

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  • Serial port and checkboxes updating

    - by hradecek
    in my app' i'm recieving data from serial port and save them into two bool arrays. And depends on these array i'm setting checkboxes. But checkboxes are not updating only when i change the tabs.... Here's how i'm doin' it(maybe there's better way how to do it) private void comboBoxCommunication_SelectionChanged(object sender, SelectionChangedEventArgs e) { if (serialPort.IsOpen) { recieveThread.Abort(); serialPort.Close(); } ComboBoxItem cbi = (ComboBoxItem)comboBoxCommunication.SelectedItem; portCommunication = cbi.Content.ToString(); serialPort.PortName = portCommunication; try { serialPort.Open(); recieveThread = new Thread(dataRecieving); prijmiThread.Start(); checkBoxI1.IsChecked = vstupy[0] ? true : false; checkBoxI2.IsChecked = inputs[1] ? true : false; checkBoxI3.IsChecked = inputs[2] ? true : false; checkBoxQ2.IsChecked = outputs[3] ? true : false; } catch (IOException ex) { MessageBox.Show(ex.ToString(), "Error!", MessageBoxButton.OK, MessageBoxImage.Error, MessageBoxResult.OK); } } private void dataRecieving() { if (serialPort.IsOpen) { int i = serialPort.ReadChar(); if (i == 'A') { inputs[0] = true; } else if (i == 'a') { inputs[0] = false; } if (i == 'B') { inputs[1] = true; } else if (i == 'b') { inputs[1] = false; } if (i == 'C') { inputs[2] = true; } else if (i == 'c') { inputs[2] = false; } if (i == 'D') { outputs[0] = true; } else if (i == 'd') { outputs[0] = false; } } }

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  • Serial Data Not Transmitted in C# Application

    - by Jim Fell
    Hello. I have a C# application wherein serial (COM1) data appears to sometimes not get transmitted. Following is a simplified snippet of my code (calls to textBox writes have been removed): try { serialPort1.Write("D"); serialPort1.Write(msg, 0, 512); serialPort1.Write("d"); serialPort1.Write(pCsum, 0, 2); } catch (SystemException ex) { /* ... */ } What is odd is that this same code works just fine when the port is configured for 115.2Kbps. However, when running at 9600bps data that should be transmitted by this code seems to not get transmitted. I have verified this by monitoring the receive flag on the remote device. No exceptions are thrown from within the try statement. Is there something else (Flush, etc.) that I should be doing to make sure the data is transmitted? Any thoughts or suggestions you may have would be appreciated. I'm using Microsoft Visual C# 2008 Express Edition. Thanks.

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  • Using a named pipe to simulate a serial port on a VMware virtual machine (linux host and client)

    - by Dave M
    Trying to write a python program to create a simulated data stream and feed it, through a named pipe, to a VMware virtual machine. The host is running Ubuntu 11.10 and VMware player 5.0.0. The Vm is running Ubuntu netbook 10.04. I am able to get the pipe working on the local machine but I am not able to get the pipe to pass data through the virtual serial port to the programs running on the virtual machine. #!/usr/bin/python import os # # Create a named pipe that will be used as the serial port on a VMware virtual machine SerialPipe = '/tmp/gpsd2NMEA' try: os.unlink(SerialPipe) except: pass os.mkfifo(SerialPipe) # # Open the named pipe NMEApipe = os.open(SerialPipe, os.O_RDWR|os.O_NONBLOCK) # # Write a string to the named pipe NMEAtime = "235959" os.write(NMEApipe, str( '%s\n' % NMEAtime )) Test to see if the python program is working on the host machine (displays 235959 if data is passing through the pipe) $ cat /tmp/gpsd2NMEA 235959 Serial port as defined in the VMware .vmx file: serial0.present = "TRUE" serial0.startConnected = "TRUE" serial0.fileType = "pipe" serial0.fileName = "/tmp/gpsd2NMEA" serial0.pipe.endPoint = "client" serial0.autodetect = "FALSE" serial0.tryNoRxLoss = "TRUE" serial0.yieldOnMsrRead = "TRUE" Test to see if the serial port in the VM is receiving data $ cat /dev/ttyS0 or $ minicom -D /dev/ttyS0 or $ stty -F /dev/ttyS0 cs8 -parenb -cstopb 115200 $ echo < /dev/ttyS0 None of these display any data from the python program.

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  • PO Communication in PDF

    - by Robert Story
    Upcoming WebcastsDate: March 29, 2010 Time: 2 pm London, 9:00 am EDT, 6:00 am PDT, 13:00 GMT Click here to register for this sessionDate: March 29, 2010 Time: 9 am London, 4:00 am EDT, 1:00 am PDT, 8:00 GMT Click here to register for this session Product Family: ProcurementSummary This one-hour session is recommended for technical and functional users who would like to know about the PO Communication functionality in procurement. Topics will include: Introduction to PO PDF communication - 11.5.10 Key ConceptsPrerequisites, Scope Overview of PDF document generation PDF solution overviewTechnical Overview of PDF generation Setup steps Triggering Points of PDF generation PO Output for communication - Concurrent programEnter PO form: View DocIsupplier portal/Contracts preview Enhancements PDF Generation in Custom LayoutsAttachments in fax communicationR12 Communication Nontext Attachments through Email Customizing templates Advantages of PDF communication Troubleshooting (Tips) A short, live demonstration (only if applicable) and question and answer period will be included........ ....... ....... ....... ....... ....... .......The above webcast is a service of the E-Business Suite Communities in My Oracle Support.For more information on other webcasts, please reference the Oracle Advisor Webcast Schedule.Click here to visit the E-Business Communities in My Oracle Support Note that all links require access to My Oracle Support.

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  • Problem with sending out variable to serial port using api JAVA

    - by sjaakensjon
    We are developing a java program for school. But we are experiencing problems with sending out a variable created by 3 sliders. The idea is that we have 3 sliders. One slider for every color. Red green and blue. The variable has to have a value between 0 and 255. Everytime the value of the slider changes is has to send a variable for the channel, that value is 1, 2 ,3. And after that it has to send the value of the slider through the serial port. Could you please help us out by creating an example program? Below is our code so far. Thanks in advance. Sjaak package main; import javax.swing.*; import javax.swing.event.*; import java.awt.*; import app.Com; import app.Parameters; public class menu{ JSlider sliderblauw; JLabel hoeveelblauw; JLabel blauw; JLabel rood; JSlider sliderrood; JLabel hoeveelrood; JLabel groen; JLabel hoeveelgroen; JSlider slidergroen; public menu(){ Frame venster = new JFrame("Color control"); JPanel blauwinstel = new JPanel(); ((JFrame) venster).setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); venster.setSize(500, 500); venster.setVisible(true); sliderblauw = new JSlider(JSlider.VERTICAL, 0, 255, 0); sliderblauw.addChangeListener(new veranderingblauw()); hoeveelblauw = new JLabel ("0"); blauwinstel.add(sliderblauw); blauwinstel.add(hoeveelblauw); venster.add(blauwinstel, BorderLayout.WEST); sliderblauw.setMajorTickSpacing(10); sliderblauw.setPaintTicks(true); JPanel roodinstel = new JPanel(); sliderrood = new JSlider(JSlider.VERTICAL, 0, 255, 0); sliderrood.addChangeListener(new veranderingrood()); hoeveelrood = new JLabel ("0"); roodinstel.add(sliderrood); roodinstel.add(hoeveelrood); venster.add(roodinstel, BorderLayout.EAST); sliderrood.setMajorTickSpacing(10); sliderrood.setPaintTicks(true); JPanel groeninstel = new JPanel(); slidergroen = new JSlider(JSlider.VERTICAL, 0, 255, 0); slidergroen.addChangeListener(new veranderinggroen()); hoeveelgroen = new JLabel ("0"); groeninstel.add(slidergroen); groeninstel.add(hoeveelgroen); venster.add(groeninstel, BorderLayout.CENTER); slidergroen.setMajorTickSpacing(10); slidergroen.setPaintTicks(true); } public class veranderingblauw implements ChangeListener{ public void stateChanged(ChangeEvent ce){ int value = sliderblauw.getValue(); String waarde_blauw = Integer.toString(value); hoeveelblauw.setText(waarde_blauw); }} public class veranderingrood implements ChangeListener{ public void stateChanged(ChangeEvent ce){ int value = sliderrood.getValue(); String waarde_rood = Integer.toString(value); hoeveelrood.setText(waarde_rood); }} public class veranderinggroen implements ChangeListener{ public void stateChanged(ChangeEvent ce){ int value = slidergroen.getValue(); String waarde_groen = Integer.toString(value); hoeveelgroen.setText(waarde_groen); }} public static void main( String[] args) { new menu(); } }

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  • Communication with HyperTerminal [ QT and WINApi ]

    - by javaAmator
    Hi! I write program to communicate with modem (it useing Hayes commands) and this is working. GUI is programmed with QT, but communication with COM port is write with winapi library. I have problem when I want to send with my program message from one computer to another, i can't send Polish chars (they are repleaced by '?'), how can I fix it ? Does anyone have idea ?? And I have one more problem, I can't send message from my program to Microsoft HyperTerminal, HyperTerminal receive something, but not that what I send. Thx for any help :) Important pieces of code: Connect with port: portHandle = CreateFile (portName, GENERIC_WRITE | GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL); GetCommState (portHandle, &dcb); switch(ui->comboBox->currentIndex()) { case 0 : dcb.BaudRate=CBR_110; break; case 1 : dcb.BaudRate=CBR_300; break; case 2 : dcb.BaudRate=CBR_600; break; case 3 : dcb.BaudRate=CBR_1200; break; case 4 : dcb.BaudRate=CBR_2400; break; case 5 : dcb.BaudRate=CBR_4800; break; case 6 : dcb.BaudRate=CBR_9600; break; case 7 : dcb.BaudRate=CBR_14400; break; case 8 : dcb.BaudRate=CBR_19200; break; case 9 : dcb.BaudRate=CBR_38400; break; case 10 : dcb.BaudRate=CBR_56000; break; case 11 : dcb.BaudRate=CBR_57600; break; case 12 : dcb.BaudRate=CBR_115200; break; case 13 : dcb.BaudRate=CBR_128000; break; case 14 : dcb.BaudRate=CBR_256000; break; } dcb.fBinary = TRUE; dcb.fParity = TRUE; dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = FALSE; dcb.fDtrControl = DTR_CONTROL_ENABLE; dcb.fDsrSensitivity = FALSE; dcb.fTXContinueOnXoff = TRUE; dcb.fOutX = FALSE; dcb.fInX = FALSE; dcb.fErrorChar = FALSE; dcb.fNull = FALSE; dcb.fRtsControl = RTS_CONTROL_ENABLE; dcb.fAbortOnError = FALSE; //dcb.ByteSize = dataBits; dcb.DCBlength = sizeof (DCB); switch(ui->comboBox_3->currentIndex()) { case 1 : dcb.Parity = EVENPARITY; break; case 3 : dcb.Parity = MARKPARITY; break; case 2 : dcb.Parity = ODDPARITY; break; case 4 : dcb.Parity = SPACEPARITY; break; case 0 : dcb.Parity = NOPARITY; break; } switch (ui->comboBox_4->currentIndex()) { case 0 : dcb.StopBits = ONESTOPBIT; break; case 1 : dcb.StopBits = ONE5STOPBITS;break; case 2 : dcb.StopBits = TWOSTOPBITS; break; } switch (ui->comboBox_2->currentIndex()) { case 0 : dcb.ByteSize = 5; break; case 1 : dcb.ByteSize = 6;break; case 2 : dcb.ByteSize= 7; break; case 3 : dcb.ByteSize = 8; break; } SetCommState (portHandle, &dcb); GetCommTimeouts (portHandle, &CommTimeouts); CommTimeouts.ReadIntervalTimeout = MAXDWORD; CommTimeouts.ReadTotalTimeoutMultiplier = 0; CommTimeouts.ReadTotalTimeoutConstant = 0; CommTimeouts.WriteTotalTimeoutMultiplier = 10; CommTimeouts.WriteTotalTimeoutConstant = 1000; SetCommTimeouts (portHandle, &CommTimeouts); Send MSG: void MainWindow::Send(char c) { do {WriteFile(portHandle, &c, 1, &cbWritten, NULL); } while (!(cbWritten)); } void MainWindow::on_pushButton_clicked() { QString str = ui->lineEdit->text(); std::string str2; ui->lineEdit->clear(); str2 = str.toStdString(); for(int i=0; i < str2.size();i++) { Send(str2[i]); //qDebug()<< str2[i]; } Send(char(13)); } Receive MSG: void ReaderThread::run() { char c; while(1) { c = Receive(); if(c==13) { emit insertPlainText("\n"); } else { emit insertPlainText(QString(c)); } } } char ReaderThread::Receive() { char c; do{ ReadFile(portHandle, &c, 1, &cbRead, NULL); } while (!(cbRead)); return c; }

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  • Bi-directional WCF Client-Server Communication

    - by Bill
    I have been working for weeks on creating a client/server to control a music-server application located on the server-side that is controlled by several client apps located across the LAN. I've been successful in getting the client-side to communicate with the Server, sending commands to operate the music-server, and through the use of callbacks, reply to the clients so that all of the client UI's can be appropriately updated. My problem is however, that I unable to figure-out how to broadcast other messages that need to be sent from the server app to the clients. I was hoping to utilize the callback method; however I have not been able to access it from the server side. Do I need to modify or create another contract that provides for communication from the server to the clients? Does the binding require modification? As I mentioned earlier, I have truly been working on this for weeks (which is beginning to feel like 'years'), and hope to get this last piece of the application working. Would someone please steer me in the right direction? Client Side SERVICE REFERENCE: <?xml version="1.0" encoding="utf-8"?> <ServiceReference> <ProxyGenerationParameters ServiceReferenceUri="http://localhost:8001/APService/mex" Name="APGateway" NotifyPropertyChange="True" UseObservableCollection="False"> </ProxyGenerationParameters> <EndPoints> <EndPoint Address="net.tcp://localhost:8000/APService/service" BindingConfiguration="TcpBinding" Contract="APClient.APGateway.APUserService" > </EndPoint> <EndPoint Address="http://localhost:8001/APService/service" BindingConfiguration="HttpBinding" Contract="APClient.APGateway.APUserService" > </EndPoint> </EndPoints> </ServiceReference> Client Side AP CONFIG <?xml version="1.0" encoding="utf-8" ?> <configuration> <configSections> <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" > <section name="APClient.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" /> </sectionGroup> </configSections> <system.serviceModel> <client> <endpoint address="net.tcp://localhost:8000/APService/service" binding="netTcpBinding" contract="APClient.APGateway.APUserService" name="TcpBinding" /> <endpoint address="http://localhost:8001/APService/service" binding="wsDualHttpBinding" contract="APClient.APGateway.APUserService" name="HttpBinding" /> </client> </system.serviceModel> <applicationSettings> <APClient.Properties.Settings> <setting name="pathToDatabase" serializeAs="String"> <value>C:\Users\Bill\Documents\APData\</value> </setting> </APClient.Properties.Settings> </applicationSettings> Server Side AP.CONFIG <?xml version="1.0" encoding="utf-8" ?> <configuration> <system.serviceModel> <behaviors> <serviceBehaviors> <behavior name="MetadataBehavior"> <serviceMetadata httpGetEnabled="true" httpGetUrl="http://localhost:8001/APService/mex" /> </behavior> </serviceBehaviors> </behaviors> <services> <service behaviorConfiguration="MetadataBehavior" name="APService.APService"> <endpoint address="service" binding="netTcpBinding" name="TcpBinding" contract="APService.IAPServiceInventory" /> <endpoint address="service" binding="wsDualHttpBinding" name="HttpBinding" contract="APService.IAPServiceInventory" /> <endpoint address="mex" binding="mexHttpBinding" name="MexBinding" contract="IMetadataExchange" /> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:8000/APService/" /> <add baseAddress="http://localhost:8001/APService/" /> </baseAddresses> </host> </service> </services> </system.serviceModel> </configuration> Server Side APSERVICE.CS namespace APService { [ServiceBehavior(ConcurrencyMode=ConcurrencyMode.Single,InstanceContextMode=InstanceContextMode.PerCall)] public class APService : IAPServiceInventory { private static List<IClientCallback> _callbackList = new List<IClientCallback>(); private static int _beerInventory = Convert.ToInt32(System.Configuration.ConfigurationManager.AppSettings["InitialBeerInventory"]); public APService() {} public int SubscribeToServer(string guestName) { IClientCallback guest = OperationContext.Current.GetCallbackChannel<IClientCallback>(); if(!_callbackList.Contains(guest)) { _callbackList.Add(guest); } else { Console.WriteLine(guest + " is already logged onto the Server."); } _callbackList.ForEach(delegate(IClientCallback callback) { callback.NotifyGuestJoinedParty(guestName); }); } public void UpdateClients(string guestName,string UpdateInfo) { _callbackList.ForEach(delegate(IClientCallback callback) { callback.NotifyUpdateClients(guestName,UpdateInfo); }); } public void SendRequestToServer(string guestName, string request) { _callbackList.ForEach(delegate(IClientCallback callback) { callback.NotifyRequestMadeToServer(guestName,request); }); if(request == "Play") { APControl.Play(); } else if(request == "Stop") { APControl.Stop(); } else if(request == "Pause") { APControl.PlayPause(); } else if(request == "Next Track") { APControl.NextTrack(); } else if(request == "Previous Track") { APControl.PreviousTrack(); } else if(request == "Mute") { APControl.Mute(); } else if(request == "Volume Up") { APControl.VolumeUp(5); } else if(request == "Volume Down") { APControl.VolumeDown(5); } } public void CancelServerSubscription(string guestName) { IClientCallback guest = OperationContext.Current.GetCallbackChannel<IClientCallback>(); if(_callbackList.Contains(guest)) { _callbackList.Remove(guest); } _callbackList.ForEach(delegate(IClientCallback callback) { callback.NotifyGuestLeftParty(guestName); }); } } Server Side IAPSERVICE.CS namespace APService { [ServiceContract(Name="APUserService",Namespace="http://AP.com/WCFClientServer/",SessionMode=SessionMode.Required, CallbackContract=typeof(IClientCallback))] public interface IAPServiceInventory { [OperationContract()] int SubscribeToServer(string guestName); [OperationContract(IsOneWay=true)] void SendRequestToServer(string guestName,string request); [OperationContract(IsOneWay=true)] void UpdateClients(string guestName,string UpdateInfo); [OperationContract(IsOneWay=true)] void CancelServerSubscription(string guestName); } } Server side - IAPServiceCallback.cs namespace APService { public interface IClientCallback { [OperationContract(IsOneWay=true)] void NotifyGuestJoinedParty(string guestName); [OperationContract(IsOneWay=true)] void NotifyUpdateClients(string guestName,string UpdateInfo); [OperationContract(IsOneWay=true)] void NotifyRequestMadeToServer(string guestName,string request); [OperationContract(IsOneWay=true)] void NotifyGuestLeftParty(string guestName); }

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  • Is 0x9B (155decimal) a special control character? Why is it missing from ascii tables?

    - by Chris
    Hi, I'm working on an embedded system, and i'm having dramas getting it to send a certain chunk of data across the serial port. I narrowed it down and found that if a 0x9B is present in the message, it corrupts the message. So i then look up 0x9b (155) on http://www.asciitable.com/, and it's missing! Isn't that a bizarre coincidence! Any ideas, is this a special character or something?

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  • dial windows serial modem from php

    - by bumperbox
    I am trying to dial a phone number from php (i have a client list in a database, and thought i could use it to ring them when i click on their name here is my code, it doesn't seem to work. I can hear the phone line click, but it doesn't seem to dial. maybe i am missing some command that needs to be sent prior to atdt? $device = "COM4"; exec("mode $device BAUD=9600 PARITY=n DATA=8 STOP=1 xon=off octs=off rts=on"); $comport = fopen($device, "r+b"); if ($comport === false) { die ("Failed opening com port"); } else { echo "Com Port Open"; } stream_set_blocking($comport, 0); $atcmd = "ATDT222222222222\r"; // dial fake number if (fwrite($comport, $atcmd ) === false) { die ("Failed writing to com port"); } else { echo "Wrote $atcmd to com port"; } fclose($comport);

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  • Java Inter Application Form Communication Observer Pattern

    - by ikurtz
    Observer pattern? Where do i get examples of this in Java (i know google but was hoping for some personal insight also.) On to a proper explanation of my issue: i have 3 forms/windows. "board" is the main form that loads as the application. "chat" is where the text chat takes place. "network" is where network connection is established. i have the game (connect4) working locally and i would like to implement a networked version of it also. my idea is maybe it is related to Observer pattern to have a thread (or something) monitoring network state during runtime and update the chat and board forms of the current network status as well as delivering received data from the network. are my ideas valid? or how should i go about establishing network and network status updates throughout the application? thank you for your input.

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  • Reading Serial Data From C (OSX /dev/tty)

    - by Jud Stephenson
    I am trying to read data from a bluetooth barcode scanner (KDC300) using C. Here is the code I have so far, and the program successfully establishes a bluetooth connection to the scanner, but when a barcode is scanned, no input is displayed on the screen (Eventually more will be done with the data, but we have to get it working first, right). Here is the program: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <fcntl.h> #include <errno.h> #include <termios.h> #include <sys/ioctl.h> int main (int argc, const char * argv[]) { // define vars int STOP = 0; //char buf[255]; if(argv[1]) { int fd = open("/dev/tty.KDC1", O_RDONLY); if(fd == -1) { printf("%s", strcat("Unable to open /dev/tty.", argv[1])); } int res; while(STOP == 0) { while((res = read(fd,buf,255)) == 0); { if(res > 0) { buf[res]=0; printf("%s:%d\n", buf, res); if(buf[sizeof(buf)]=='\n') break; } } } } return 0; } If anyone has any ideas, I am at a loss on this so far. If it is any help, I can run screen /dev/tty.KDC1 and any barcodes scanned on the scanner appear in the terminal, I just can't do anything with the data. Jud

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  • Communication between modules

    - by David Elentok
    I have an application that consists from the following three modules: Search (to search for objects) List (to display the search results) Painter (to allow me to edit objects) - this module isn't always loaded (Each object is a figure that I can edit in the painter). When I open an object in the painter it's added to the objects that are already in the painter and I can move it and alter it. I'm using an object similar to the EventAggregator to communicate between the modules. For example, to show the search results I publish a "ShowList" event that is caught by the List module (I'm not sure this is the best way to do this, if anyone has better idea please comment...). One of the features of the search module requires it to get the selected object in the painter (if the painter is available), and I'm not sure what would be the best way to do that... I thought of these solutions: Whenever the selected object in the painter changes it will publish a "PainterSelectedObjectChanged" event which will be caught by the search module and stored for later use. When the selected object is needed by the search module it will publish a "RequestingPainterSelectedObject" event which will be caught by the painter module. The painter module will then set the "SelectedObject" property in the EventArgs object, and when the publish is complete and we're back in the search module we will have the painter's selected object in the EventArgs object. What do you think? what is the right way to do this?

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  • Communication between EJB3 Instances (JEE inter-bean communication) possible?

    - by Hank
    I'm designing a part of a JEE6 application, consisting of EJB3 beans. Part of the requirements are multiple parallel (say a few hundred) long running (over days) database hunts. Individual hunts have different search parameters (start time, end time, query filter). Parameters may get changed over time. Currently I'm thinking of the following: SearchController (Stateless Session Bean) formulates a set of search parameters, sends it off to a SearchListener via JMS SearchListener (Message Driven Bean) receives search parameters, instantiates a SearchWorker with the parameters SearchWorker (SLSB) hunts repeatedly through the database; when it finds something, the result is sent off via JMS, and the search continues; when the given 'end-time' has reached, it ends What I'm wondering now: Is there a problem, with EJB3 instances running for days? (Other than that I need to be able to deal with container restarts...) How do I know how many and which EJB instances of SearchWorker are currently running? Is it possible to communicate with them individually (similar to sending a System V signal to a unix process), e.g. to send new parameters, to end an instance, etc..

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  • VB - Server communication

    - by Bubby4j
    How would I make a Visual Basic application talk to a web server? Someone will press something on the site and I want the application to display the information that the web site passes along to it.

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  • Problem with object serialization in Applet-Servlet communication

    - by Bruce
    Hi guys, I spent a lot of time on thinking what is wrong with the following code. I send the object from my applet to servlet and then I read the object from servlet. Everything goes fine till reading serialized object from the servlet - I got IOException. Thank you in advance! Here is the code: Applet: try { URL servletURL = new URL(this.getCodeBase().getProtocol(), this.getCodeBase().getHost(), this.getCodeBase().getPort(), "/MyApplet"); URLConnection servletConnection = servletURL.openConnection(); servletConnection.setDoInput( true ); servletConnection.setDoOutput( true ); servletConnection.setUseCaches( false ); servletConnection.setRequestProperty( "Content-Type", "application/x-java-serialized-object" ); ObjectOutputStream output; output = new ObjectOutputStream( servletConnection.getOutputStream( ) ); output.writeObject( someObject ); output.flush( ); output.close( ); ObjectInputStream input = new ObjectInputStream( servletConnection.getInputStream( ) ); // Here I got the exception myObject = ( SomeObject ) input.readObject( ); } catch (java.io.IOException ioe) { System.err.println(ioe.getStackTrace()); } catch (Exception e) { System.err.println(e.getStackTrace()); } Servlet: response.setContentType("application/x-java-serialized-object"); try { ObjectInputStream inputFromApplet = new ObjectInputStream(request.getInputStream()); SomeObject myObject = (SomeObject) inputFromApplet.readObject(); ObjectOutputStream outputToApplet = new ObjectOutputStream(response.getOutputStream()); outputToApplet.writeObject(myObject); outputToApplet.flush(); } catch(Exception e) { // ... }

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  • Communication between (Desktop/Smartphone) Application and Web Application

    - by erlord
    Hi all I wonder what is the commonly used method and protocol for a, say, smartphone application to send its data to a web application (where these data should be proceeded and stored). My naive beginner's approach would be something like this: From my smartphone app, use a framework encoding my data object into a json object Send this object via http to a listener addressed by a dedicated URL On the server side, use a JSON parser and store it via ORM etc. into a database Questions: Is this too naive? 2a. If yes: What is the appropiate way to tackle this workflow? 2b. If no: What frameworks to use in JAVA for serializing/deserializing to/from JSON objects? Any example for a json listener in the web? Tutorial for a http-protocol based Java listener? Thanks for all answers and suggestions in advance. Regs Me

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  • Python: Serial Transmission

    - by Silent Elektron
    I have an image stack of 500 images (jpeg) of 640x480. I intend to make 500 pixels (1st pixels of all images) as a list and then send that via COM1 to FPGA where I do my further processing. I have a couple of questions here: How do I import all the 500 images at a time into python and how do i store it? How do I send the 500 pixel list via COM1 to FPGA? I tried the following: Converted the jpeg image to intensity values (each pixel is denoted by a number between 0 and 255) in MATLAB, saved the intensity values in a text file, read that file using readlines(). But it became too cumbersome to make the intensity value files for all the 500 images! Used NumPy to put the read files in a matrix and then pick the first pixel of all images. But when I send it, its coming like: [56, 61, 78, ... ,71, 91]. Is there a way to eliminate the [ ] and , while sending the data serially? Thanks in Advance! :)

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