C# Serial Port Overrun Error
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C# Serial Port Buffer Overflow
APIs and reference Dev centers Retired content Samples We’re sorry. The content you requested has c# serial port example been removed. You’ll be auto redirected in 1 second. .NET Framework Class Library System.IO Namespaces System.IO.Ports System.IO.Ports SerialError Enumeration SerialError Enumeration SerialError Enumeration Handshake Enumeration c# serial port read example Parity Enumeration SerialData Enumeration SerialDataReceivedEventArgs Class SerialDataReceivedEventHandler Delegate SerialError Enumeration SerialErrorReceivedEventArgs Class SerialErrorReceivedEventHandler Delegate SerialPinChange Enumeration SerialPinChangedEventArgs Class SerialPinChangedEventHandler Delegate SerialPort Class StopBits Enumeration TOC Collapse the table of content Expand the table of content This documentation is archived and is not being maintained. This documentation is archived and
Visual C# Serial Port
is not being maintained. SerialError Enumeration .NET Framework (current version) Other Versions Visual Studio 2010 .NET Framework 4 Visual Studio 2008 .NET Framework 3.5 .NET Framework 3.0 .NET Framework 2.0 Specifies errors that occur on the SerialPort object.Namespace: System.IO.PortsAssembly: System (in System.dll)Syntax C#C++F#VB Copy public enum SerialError MembersMember nameDescriptionFrameThe hardware detected a framing error.OverrunA character-buffer overrun has occurred. The next character is lost.RXOverAn input buffer overflow has occurred. There is either no room in the input buffer, or a character was received after the end-of-file (EOF) character.RXParityThe hardware detected a parity error.TXFullThe application tried to transmit a character, but the output buffer was full.RemarksThis enumeration can be useful when handling the ErrorReceived event to detect and respond to errors when communicating data through a SerialPort. You examine the type of error by retrieving the EventType property of the SerialErrorReceivedEventArgs class. The EventType property contains one of
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Visual Basic Serial Port
Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join https://msdn.microsoft.com/en-us/library/system.io.ports.serialerror(v=vs.110).aspx them; it only takes a minute: Sign up Serial Port Returning Invalid Data up vote 1 down vote favorite I have a weighing machine that is connected to a computer using a serial port. It is a very old machine and we are trying to get the weights off it and save in a database. The weight returned by http://stackoverflow.com/questions/14253739/serial-port-returning-invalid-data the machine has some invalid characters like ?, and the weight is displayed as ??2?0, where it should have been 02220. I understand it has something to do with encoding as results on a web search suggest. But I can not figure out what exactly am I missing. Here is my code: private void port_DataReceived(object sender, SerialDataReceivedEventArgs e) { // This method will be called when there is data waiting in the port buffer // Read all the data waiting in the buffer // string data = comport.ReadExisting(); // Display the text to the user in the Rich Text Box Log(LogMsgType1.Incoming, s); } public void OpenThisPort() { bool error = false; // If the port is open, close it if (comport.IsOpen) { comport.Close(); } else { comport.BaudRate = int.Parse("1200"); comport.DataBits = int.Parse("8"); comport.StopBits = StopBits.One; comport.Parity = Parity.None; comport.PortName = "COM1"; delStart = 0; delLength = 9; comport.RtsEnable = true; comport.DtrEnable = true; comport.Encoding = System.Text.Encoding.GetEncoding(28591); } How do I determine exactly which encoding will be applied? Any idea what I'm missing here? c# .net enc
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers http://stackoverflow.com/questions/4737654/serialport-communication-questions or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it http://www.pcreview.co.uk/threads/serial-port-overrun-error.1306405/ only takes a minute: Sign up SerialPort communication questions up vote 2 down vote favorite I know SerialPort communication in .NET is designed to send the DataReceived event to the receiver when data is available and reach the threshhold. Can serial port we not use that DataReceived event and start a thread in the receiver side to freqenutly call one of those ReadXXX methods to get data? What will happen if receiver is much slower than the sender? The SerialPort buffer will overflow (data lost)? c# .net serial-port share|improve this question edited Jan 19 '11 at 16:19 casperOne 58k10126202 asked Jan 19 '11 at 16:12 5YrsLaterDBA 8,1172387169 add a comment| 3 Answers 3 active oldest votes up vote 1 down vote There's c# serial port little point in doing this, just start the reader thread yourself after you open the port and don't bother with DataReceived. Doing it your way is difficult, tough to cleanly unsubscribe from the DataReceived event after you started the thread, especially at the very moment data is being received. You can't afford to have them both. share|improve this answer answered Jan 19 '11 at 19:29 Hans Passant 653k819531598 add a comment| up vote 0 down vote That works, in fact it's one of the ways I used in my question Constantly reading from a serial port with a background thread. For your scenario you could listen to the DataReceived event, then start a thread that calls ReadExisting on the port to get all currently available bytes. You can also check how many bytes are waiting in the receive buffer by looking at the SerialPort.BytesToRead property. As for your receive buffer overflowing, a) it's big enough (you can check with the SerialPort.ReadBufferSize property) and b) this isn't 1982, so CPUs are fast enough to process data from the port so that it doesn't have time to fill up (certainly much faster than the serial data rate). share|improve this answer answered Jan 19 '11 at 16:18 Aphex 4,33722244 add a comment| up vote 0 down vote The function of the thread that read serial port can be as this: private void ThreadRx() { while (true) { try { if (th
Guest I'm using OpenNETCF.IO.Serial.Port to access the serial port (not Bluetooth). If the other device (that is connected with the Pocket PC) sends more than 64 bytes, the CommEventThread-method throws a UART Error:Overrun error. If the other device sends the data in blocks that are shorter than 65 bytes and waits a short time between sending two blocks, everything works fine. This occurs only on my T-Mobile MDAII device. When I execute the same program on my IPAQ 2210 the error doesn’t occur. I also tried different values for rxBufferSize, but it doesn’t help. Does anyone know that problem? Sebastian Zenker, Jul 17, 2004 #1 Advertisements Chris Tacke, eMVP Guest My guess is that the MDAII's UART has a 64-byte buffer and it's driver is slow to pull data out of the buffer, so when you send > 64-bytes, the buffer fills and overruns before the driver pulls it back off, so it sees the overflow and raises the error. Are you also seeing data loss when you get the overflow? -Chris "Sebastian Zenker" <> wrote in message news:cdbbcg$7av$03$-online.com... > I'm using OpenNETCF.IO.Serial.Port to access the serial port (not > Bluetooth). > If the other device (that is connected with the Pocket PC) sends more > than 64 bytes, the CommEventThread-method throws a UART Error:Overrun > error. If the other device sends the data in blocks that are shorter > than 65 bytes and waits a short time between sending two blocks, > everything works fine. > > This occurs only on my T-Mobile MDAII device. When I execute the same > program on my IPAQ 2210 the error doesn’t occur. > > I also tried different values for rxBufferSize, but it doesn’t help. > > Does anyone know that problem? Chris Tacke, eMVP, Jul 17, 2004 #2 Advertisements Sebastian Zenker Guest Yes, the MDA lost data. For example: When the other device sends 2 blocks of 100 byte, the MDA will only receive 2x64 bytes instead of 2x100 bytes and 2 overrun errors occur. I also suppose that the driver is to slow. But what can I do? I just write a small program that only consists of the Port-class and a small GUI to test it (so that I can be sure that no other thread of my application will devour the whole cpu time). Is there maybe a registry setting, to give the driver more cpu time? I also searched if there is a new firmware-update available, but it's up to date. I'm using the serial port with 38400 Baud, so I think that there must be a possibility to use it. Otherwise it make no sence to have it. Thank you Sebastian Chris Tacke, eMVP wrote: > My guess is that the MDAII's UART has a 64-byte buffer and it's driver