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serial port configuration help.read() and write() return -1 and serial comunication stop.why?
You have configured the file descriptor to be in non-blocking mode. This means that when you write() (and read, for that matter) it will not block waiting for the write to finish if the port is already busy. Instead it will return -1 and set errno to EAGAIN (or EWOULDBLOCK). So, to fix this: fd = open("/dev/ttyUSB1", O_RDWR | O_NOCTTY | O_NDELAY); Remove O_NDELAY. O_NDELAY is an alias for O_NONBLOCK, and this is what makes read() and write() behave like you see. fcntl(fd, F_SETFL, FNDELAY); This is the same thing as O_NDELAY (in fact, FNDELAY is a compatibility alias for O_NDELAY, which is an alias for O_NONBLOCK), it just sets the flag again. fcntl(fd, F_SETFL, O_SYNC); This you do not want. But I do not think it hurts things significantly. It will cause writes to

Categories : C

ssis smtp mail task /connection ,how to mention the port number if the port number is not 25
You need to configure your SmtpClient to use ssl like: mySmtpClient.EnableSsl = true this should do the trick. EDIT: To use the correct credentials use: mySmtpClient.Credentials = new System.Net.NetworkCredential("yourusername", "yourpassword")

Categories : Sql Server

update tkinter label from serial data whenever there's new data from serial port python 3.x
You can run your GetTemp() method in a seperated thread from _thread module. The thread is called with the Tkinter method after(). In following example I substituted your GetTemp() with a randomn number generated. import tkinter import tkinter.messagebox import time import random import _thread class Menu: def __init__(self): self.main_window = tkinter.Tk() self.main_window.title("Room Light System") self.main_window.geometry("1200x600") #Frames self.frame_2 = tkinter.Frame(self.main_window, bg='Orange') # Receiving DATAs #ReceiveLabel self.ReceiveLabel = tkinter.Label(self.frame_2, text = 'Received DATAs', bg = 'White',

Categories : Python

Qt Serial Port communication
From this forum, it appears that sometimes not all the data gets sent, and whatever does gets sent has a '' appended to it. So if cd /applica'' got sent, then the port->readAll() would stop there, because it thinks it has read everything. One suggested answer on that forum was to read line by line, which your code almost does. So I think in your case, you can change your code to: void Logic::onReadyRead(){ QByteArray incomingData; if(port->canReadLine()) { incomingData = port->readLine(); QString s(incomingData); emit dataAvailable(s);// this is a Qt slot if you don't know what it is. qDebug() << "in:"<< s.toLatin1(); } } void Logic::writeToTerminal(QString string ) { string.append( " "); port->wr

Categories : C++

Sending ENQ, id, CR, and LF to Serial Port using C#
Use the (serial port write method ) with a byte array of 5,30,13,10. byte[] buf = new byte[] { 5, 30, 13, 10 }; sp.Write(buf, 0, buf.Length);

Categories : C#

C# Serial Port Issue
Have you tried disposing the SerialPort object instead of closing it? http://msdn.microsoft.com/en-us/library/system.io.ports.serialport.errorreceived.aspx If a SerialPort object becomes blocked during a read operation, do not abort the thread. Instead, either close the base stream or dispose of the SerialPort object.

Categories : C#

PHP Serial Port Access
Try this below code hope it helps, Note : uses php_serial.class.php Code : <?php require("php_serial.class.php"); $serial = new phpSerial; // First we must specify the device. This works on both linux and windows (if // your linux serial device is /dev/ttyS0 for COM1, etc) $serial->deviceSet("/dev/ttyS0"); // We can change the baud rate, parity, length, stop bits, flow control $serial->confBaudRate(9600); $serial->confParity("none"); $serial->confCharacterLength(8); $serial->confStopBits(1); $serial->confFlowControl("none"); // Then we need to open it $serial->deviceOpen(); // To write into $serial->sendMessage("AT+CMGF=1 "); $serial->sendMessage("AT+cmgs="+912709345x23" "); $serial->sendMessage("Hi, This is the sms that I sent to you usin

Categories : PHP

Reading the Serial Port
im trying to figure out why when there is weight will it not scan, note that if I scan 7 times it may catch it once 1 out of 10 times You'll need to debug your code, put a break point &/or Debug.Print(data) statements to see why only one out of ten times it meets the first if condition: if (comport.BytesToRead > 0) { if (data.StartsWith("S08")) { textBox1.Text = data.Substring(4).Trim(); timer3.Stop(); scan(); timer3.Start(); } if (data.StartsWith("S144")) { if (data == "S1440000") { label8.Text = "0.00"; } else { string data3 = data.Substring(4); data3 = data3.Trim(); var data4 = data3.Insert(2, "."); string data5 = double.Parse(d

Categories : C#

Receiving only different values from serial port
availablePlayers[plIndex] = rx_data; This will crash your code the second time you receive a string. Unfortunately you are also catching the IndexOutOfRangeException and close the port. Which will completely deadlock the code, SerialPort.Close() can only complete when the event handler has returned. Specific counter-measures: use a List<string> instead of a string[] remove try/catch from your code, it cannot ever do anything but make your program fail without a way to recover write an event handler for AppDomain.CurrentDomain.UnhandledException to provide a diagnostic when your program dies on unexpected exceptions get familiar with the Debug + Windows + Threads debugger window. It allows you to see what's going on in other threads, you would have seen the deadlock.

Categories : C#

C# waiting for the data on serial port
If this is a Console application, you can use things like Console.ReadLine() etc. after calling the appropriate function of the COM Port component to start listening asynchronously. If this is a WinForms application. The message loop will of course keep showing your current form. In that case you can call asynchronous listening function in the Form_Load event or behind a button click. The key point here is that you should call the asynchronous version of the listener function. There is no need to use delays or timers in that case.

Categories : C#

Send Hex data to a serial port?
basically, what you're doing is right given your GPS reads actually hexadecimal bytes. But it may as well read string encoded hexadecimal values, so be sure of that. So from what you tell, I'd say you're writing to it correctly. And you don't say how you open the serial port, but be careful to use termios and set the connection up correctly, or you may get issues. You shall not just open the port like a standard file. If you haven't done it yet, have a good read of this!

Categories : C++

testing bytes from a serial port
from pyserial's documentation: Changed in version 2.5: Returns an instance of bytes when available (Python 2.6 and newer) and str otherwise. so I tested: >> bytes(0xbe) == 0xbe False but if you convert it to int: >> int(bytes(0xbe)) == 0xbe True as this stackoverflow question shows, the bytes type is included by [PEP-31373]. It is like a bytearray for python3, but just an alias for str in python2. So, basically, just treat pyserial's output as a str while you're doing python2 code.

Categories : Python

Send Hex Bytes To A Serial Port
You cannot sent an integer over a serial line.... you can only sent BYTES (7-8 bit)! You need to choose what you want to do: Sent characters: So the "number" 12 will be converted into the bytes _serialPort->Write(12.ToString()); // => 0x49, 0x50 Sent the integer (4 bytes) as little endian auto data = System::BitConverter::GetBytes(12); _serialPort->Write(data, 0, data->Length); // => 0x0c, 0x00, 0x00, 0x00 Or you write just a single byte: auto data = gcnew array<System::Byte> { 12 }; _serialPort->Write(data, 0, data->Length); // => 0x0c Or write an byte array: auto data = gcnew array<System::Byte> { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x02, 0xBF, 0x00, 0x00, 0xBD }; _serialPort->Write(data, 0, data->Length); // => 0xFF 0xFF 0xFF 0xFF 0xFF 0

Categories : C++

Serial Port does not receive whole data in C#
the TextBox.CheckForIllegalCrossThreadCalls = false; makes me very suspicious, I think that is what is breaking your program, simply just invoke to update the text box properly and I think it will work. Just change the event code to the following: void sp_DataReceived(object sender, SerialDataReceivedEventArgs e) { if(textbox1.InvokeRequired) { textbox1.Invoke(new SerialDataReceivedEventHandler(sp_DataReceived), sender, e); } else { var valueOfPort = sp1.ReadExisting(); textBox1.AppendText(valueOfPort); } } What this will do is check if you are running on the correct thread, if not it restarts the function again on the UI thread with the same arguments. Also be sure to remove the TextBox.CheckForIllegalCrossThreadCalls = false; UPDATE:

Categories : C#

Selecting serial port in Qt(Linux)
You can construct a serial port object using QSerialPort port("/dev/ttyUSB0"). This QSerialPort constructor accepts port name in the form it's present in QSerialPortInfo::portName(). It's not documented that this name is in the "/dev/ttyUSB0" form but it appears to be so.

Categories : Qt

Serial Port Data Issue
I had burnt a code into the Sender node to send 1s continuously to the Receiver. But what i see is that even after burning a new code into the Sender to send different values, i keep getting the 1s in the receiver end and not the latest values. How do i get over this problem? You shall reflash your Arduino. Try reflashing with 2s instead of 1s, and back, you'll see it'll stop sending 1s. Is there a way to flush the previous unwanted data? The data itself is gone away on every unplugging of your Arduino. It looks like your Arduino code did not get uploaded to the board, either you had a connection problem, or your new arduino code is not compiling. Have a good look at the error message the IDE compiler should be returning.

Categories : Java

Locking Linux Serial Port
I was able to fix the issue with use of the flock() function. Use of the structure and fcntl() wasn't working for me for some reason. With use of flock() I was able to add two lines of code and solve my issue.

Categories : C

Socket connection to serial port
Try with these two links ,are awesome: http://wirespeed.xs4all.nl/mediawiki/index.php/Udev_rules_file_for_Arduino_boards http://wirespeed.xs4all.nl/mediawiki/index.php/Cat_ttyUSB0

Categories : PHP

Multithreading and Listening Serial Port
You misunderstand what is going on. SerialPort.ReadLine() does not use a thread. It is your DataReceived event handler that runs on another thread. Necessary so that the SerialPort can notify your code about received data as quickly as possible without having to wait for your UI thread to go idle. Which does indeed mean that you cannot directly update your UI from your event handler, you'll get an InvalidOperationException when you try anyway. The DataReceived event is certainly there to help you avoid freezing your UI. There are too few hints in your question to know what your real problem might be. One issue could be using Control.BeginInvoke() too often, flooding the UI thread with invoke requests so it doesn't get around to doing its regular duties. Like responding to input and

Categories : C#

Serial Port value not a valid ascii
print chr(0xb0-0x80) 0 print chr(0xae-0x80) . etc - I suspect that you data length is set incorrectly, (data bits).

Categories : Python

Writing to serial port in Android NDK
Found that android has a serialport-api and the sample app provided in the project site helped me find out the port number of my android device. The links are this and this.

Categories : Android

Share Serial Port on Linux
I believe it is possible for multiple applications to access a TTY device simultaneously. The fact that you are performing read operations from one userspace application and write operations from another means you are unlikely to encounter a problem. To verify this you can read from a serial into a serial device using the console: cat /dev/ttyS0 If you open another terminal, you can write to the device without any problem: echo "stuff" > /dev/ttyS0

Categories : C++

Incomplete Serial Port Read C#
This is expected behaviour with byte streams. Loop round the read and pump however many bytes received one-by-one into your ProtocolUnit class instance, (or whatever), until it is complete and verified.

Categories : C#

c# Serial-port: Receiving some echo
The ASCII character 8 is a backspace character. It appears that the program on the other end of your serial cable is trying to erase characters entered at its prompt before reprinting the came thing, with your new character added to the end. Change your program to detect when ASCII 8 is received, and then delete the last character and move the cursor position back one. Might be tricky if you backspace through a new-line... I would ignore it if you're already at the left edge. You might see other things too. There is a BEL character (7?) that should cause the terminal to beep. There are other characters for other things... It's possible too, if you start seeing other weird things, that this device expects the user (you) to handle VT100 or ANSI terminal commands. You'll probably see thing

Categories : C#

List of the connected Serial port C Qt
You should use QSerialPort Look at the enumerator example to know how If you use Qt4, look here

Categories : C++

Serial port communication and web application
I would imagine there could be a potential problem, if second request is made while the first is still writting to the serial port. You could create a standalone application that would receive data over tcp/ip (or named pipes or other means of ipc), buffer it in queue and send it forward to serial port.

Categories : Java

Read bytes from serial port
You are going about this the wrong way. Clicking a button will open serialPort1; sure. It will then try to read the buffer. But you only opened the port in the same method! Take a look at this tutorial: http://www.dreamincode.net/forums/topic/35775-serial-port-communication-in-c%23/ It takes you through the entirety of serial communications in C#. You certainly don't want to be opening and reading the port only on a button press event handler.

Categories : C#

Serial port ping functionality
It just isn't quite the same problem as having to use Ping to find if a server that's located a thousand miles away is online. With serial ports you just look at the other end of the cable, you rarely have to walk more than a few feet. There's also nothing similar to having a stateful connection like TCP. All you can really do is look at the hardware handshake signals. The SerialPort.DsrHolding gives you the state of the Data Set Ready signal. A properly implemented serial device uses that signal to say that it is powered-on. CtsHolding is an additional signal, it says that it is ready for you to send data. They normally have to be both turned on before you consider sending anything. These handshake signals are not always properly implemented. You may well have a problem if the se

Categories : C#

Reading from serial port with while-loop
Your problem is that Read() will return whenever it has some data - it won't wait for all the data. See the io.Reader specification for more info What you want to do is read until you reach some delimiter. I don't know exactly what format you are trying to use, but it looks like maybe x0a is the end delimiter. In which case you would use a bufio.Reader like this reader := bufio.NewReader(s) reply, err := reader.ReadBytes('x0a') if err != nil { panic(err) } fmt.Println(reply) Which will read data until the first x0a.

Categories : Go

Send TTL signal through serial port in Matlab
I don't think you can output TTL using the actual serial port, as that is RS-232, not TTL logic levels. If you're using the serial port, you'll need a converter, like this. If you're using an FTDI driver/USB cable, that already outputs TTL logic levels, and the code looks good to me, which means the bug is probably on the device end.

Categories : Matlab

Java not sending correctly to Serial Port
A few problems. The Java code sets 38400, the Arduino 9600 baud. The getBytes() is not ensured to give you ASCII. It will return whatever your default encoding is subject to a bunch of caveats. In general, you cannot count on this method and should always prefer explicit control of the encoding. There is endless people burned by this, here is just one random reference. try getBytes("UTF-8") You have no terminator that defines the end of the number. You may think "3000" is sent, but you should think in terms "3" is sent, then "0", then "0", then "0". On the Arduino side, the call to Serial.available() can occur at any time in this sequence. So the code could get to the parseInt() line when just the "3" has been received. The Arduino is spinning through the loop() much faster tha

Categories : Java

UI freezes while reading data on serial port
It sounds as though you have either set up your Thread object(s) incorrectly, or you are passing feedback back to the UI too often. If you are not comfortable about working with Thread objects directly, perhaps the BackgroundWorker class might help you. Check out the BackgroundWorker Class page at MSDN.

Categories : Wpf

Prolific PL2303 serial port to 250000bps
Other posts recommend something like: // Set baud system("stty -F /dev/ttyUSB0 250000 cs8 -cstopb -parity -icanon min 100 time 1"); // Open file FILE *ComPort = fopen("/dev/ttyUSB0", "r+"); What does happen when you try setting the baud to 250kbps?

Categories : Linux

How to clear serial port BytesAvailable by using Matlab?
You can try flushinput(Serial_Port_obj) function in matlab. This function clears all the data that are stored in the input buffer. Otherwise you can use fread(Serial_Port_obj,Serial_Port_obj.BytesAvailable). The latter just reads instantly all the data stored again in the input buffer. But as soon as the buffer clears out, data from the phone will start again to flow in the computers buffer. Simply think it like this: PhoneDataToTransmitOnThePhone -> SoftwareBufferOnThePhone -> HardwareBufferOnThePhone -> HardwareBufferOnThePC -> SoftwareBufferOnThePC -> PhoneDataToTransmitOnThePC If you also want to delete data that are stored on the phone buffer I can't help you with that. Note that all the buffer are FIFO (First In -> First Out).

Categories : Matlab

write a string to a serial port in java
Try to use getBytes() method which returns byte array. OutputStream mOutputToPort = serialPort.getOutputStream(); String mValue = "ABCDEFG"; System.out.println("beginning to Write . "); Byte[] data = mValue.getBytes(); for(int i=0;i<data.length;i++){ mOutputToPort.write(data[i]);} System.out.println("AT Command Written to Port. "); mOutputToPort.flush();

Categories : Java

How to use a serial port to communicate with an RFID reader
Task: Write/send data & read/receive data over UART to/from SL031 using microcom. Problem: Your device expects data/commands in hexadecimal format and, as far as I know, microcom does not directly support sending data in hexadecimal format. Solution: To write/send: Use a hex editor, Bless Hex Editor for instance, to write a series of commands you want to send to SL031. Redirect/pipeline this data, using basic shell commands, to microcom. To read/receive: Capture the data of microcom in a file and analyze it with a hex editor. You can do this by redirecting/pipelining the output of microcom to a log file. Hope this helps. If it does kindly accept the answer :) Ask me if you need further clarification.

Categories : Linux

Sending commands serial port, MVC Application
I assume you're using an ASP.NET MVC web application and now want to access the client's (browser machine) serial port. This isn't possible with ASP.NET MVC without additional client software like a signed Java Applet or other software installed on the client machine (like a service, browser plugin or background application.) This thread may be of use: How to read from Serial port in a webpage

Categories : Java

C# Serial Port Check if Device is Connected
I would agree that is a hacky because any device could be connected and sending '>'; but that doesn't mean its your device. Instead, be dynamic and use something like SerialPort.GetPortNames and WMI Queries to interrogate the devices plugged into the COM ports. You could use this example as a starting point. After reading documentation and examples, you should be able to create a list of all device information that registers drivers on the computer and their connected COM port. Edit: Since the device doesn't register itself, consider looking at the product drivers for Visual Studio that might make your job a lot easier.

Categories : C#

C# reading from serial port and storing it in csv in different coloumns
You seem to have some problems in the way you are writing the string. First of all you are appending a new line per split in your incomming data. You want to append them as a comma separated strings instead. Another thing is that you count it wrong. You will omit the last object in your incomming string array. Try the following: char[] store_array = new char[list_data.Length-1]; store_array = list_data.ToArray(); string filePath = @"c: emp est_no_8.csv"; StringBuilder sb = new StringBuilder(); string char_array_to_str = new string(store_array); string[] spilt_value = char_array_to_str.Split('*'); for (int index = 0; index < spilt_value.Length; index++) { if(index == spilt_value.Length-1) sb.Append(spilt_value[index]); else sb.Append(spilt_value[index] + ","); } File.

Categories : C#

Serial port not reading complete transmission
ReadFile has no way to detect what a "block of data" is. You should not expect it to understand your data or the timing of that data. The only fix for this issue is for you to process whatever it gives you, using your own knowledge of the data to divide it up into "blocks" for further processing. If you get a partial block keep it, and append to it with the next read. There is no need to call WaitCommEvent for data. ReadFile will wait for data. But give it a suitably sized buffer and ask for a lot more than one byte at a time. It's extremely inefficient to call it for only one byte. Select the requested count and the timeouts so that ReadFile will return within an acceptable time, whether there is data or not.

Categories : C++



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