How To Read Data From Serial Port In C .net
So it looks like the connection reads the data in the middle of the package (to be exact: 3 bits too late). What can i do? I want to avoid a solution where this error is fixed later in the code while reading the packages like this, because I don't know if the the shifting error gets worse when I edit the reading code later, which I will do most likely.
how to read data from serial port in c .net
Your event handler is being called when data is available to read -- but you are only consuming two bytes of the available data. Your event handler may only be called every 1024 bytes. Or something similar. You might need to consume all the available data in the event handler for your program to continue as expected.
Serial ports provide an easy way to communicate between many types of hardware and your computer. They are relatively simple to use and are very common among peripherals and especially DIY projects. Many platforms such as Arduino have built in serial communication so they are really easy to set up and use. Many times you may want your project to communicate with your computer in order to have a cool interactive output, a neat sensor that passes data to your computer, or anything else you could possibly dream up. In this tutorial, I will walk you through how to interface to a serial port on the computer side of things, using Microsoft's . net framework. The code examples in this tutorial are in C#, but can be easily transferred to Visual Basic, or Visual C++. This tutorial assumes that you have a very basic understanding of object oriented programing, and whatever language you choose to program in. Since we are mainly going to be using the System.IO.Ports.SerialPort class, HERE is a link to the full documentation by MSDN if you want to check out the rest of the class. I also found a great article explaining how to fix several common bugs relating to serial ports. Check it out if you get stuck with any odd errors. Feel free to post questions or feedback! I am always happy to hear constructive comments so I can make improvements.
I hope this is helpful to you and your next project. This was something that I personally struggled to figure out so I hope that this will help you have an easier time learning how to interface over a serial port. Feel free to post comments, questions and feedback below.
Thanks very much for responding, I wasn't sure how old this post was. But yes, the meat & potatoes of the program relies on listening to these com ports but it has to listen to all of them at the same time which I guess would be using the event handler. Since the ports most likely would be different on other systems using this program, I have a separate program that reads and writes configuration data to an SQL database. Once the main program is launched, it reads in the configuration info of the com ports from the sql database. These com ports are connected to several 3rd party databases, so I need to send heartbeats to each one at time intervals and expect to receive an acknowledgement back to make sure the far end is listening. I have a server connected to the port that would send a telephone number to this program, the program would look at the number, compare it against a list to determine which 3rd party database it belongs to and then send it out that comm port. The 3rd party database at the far end would then send that customers address information to the program, the data would be rearranged, and then sent back to the server requesting it. (in a nutshell) We've used software like this in the past but now with the XP & server 2003 going away we need to write our own, I've designed stuff in VB6 before but never used the MSComm so I'm sort of a newbie to all of this. I'll be doing it in .net though so I've got my hands full learning the intricacies. Sorry to talk your ear off, have a nice night -Steve (I tried to upload a diagram don't know if it took)
could you please share your code on how we can send data from NODMCU to serial port and get data from serial port using C# MVC Web Application. I want to make the project. It will a great favor if you pay heed to my request.Thanks in Advance.Email: firstname.lastname@example.org
Thanks for an informative guide, I am looking to read port configurations from an SQL database, assign them to multiple com ports, and then listen on each port for data, then act upon that data. Is it possible to dimension the serial port object into an array of objects? I haven't had a chance to play around with it yet but thought I would ask first. Thanks in advance -Steve
If I understand your question correctly, what you can do is create and array or collection (List, ArrayList, etc.) to hold and control all of the SerialPort objects. From there polling would be easy (yet time consuming for your program) with a simple for loop. For event driven reading, the process is a little different and would involve the use of delegates in order to accommodate the multiple ports.
The following code example demonstrates the use of the SerialPort class to allow two users to chat from two separate computers connected by a null modem cable. In this example, the users are prompted for the port settings and a username before chatting. Both computers must be executing the program to achieve full functionality of this example.
Use this class to control a serial port file resource. This class provides synchronous and event-driven I/O, access to pin and break states, and access to serial driver properties. Additionally, the functionality of this class can be wrapped in an internal Stream object, accessible through the BaseStream property, and passed to classes that wrap or use streams.
This article will demonstrate how to write and receive data from a device connected to a serial port in C# and .NET. We will be writing the received data to a TextBox on a form, so this will also deal with threading.
Now, we are ready to receive the data. However, to write this data to the TextBox on a form, we need to create a delegate. .NET does not allow cross-thread action, so we need to use a delegate. The delegate is used to write to the UI thread from a non-UI thread.
We can now receive data from a serial port device and display it on a form. Some devices will send data without being prompted. However, some devices need to be send certain commands, and it will reply with the data that the command calls for. For these devices, you will write data to the serial port, and use the previous code to get the data that will be sent back. In my example, I will be communicating with a scale. For this particular scale, sending the command "SI\r\n" will force it to return the weight of whatever is on the scale. This command is specific for this scale. You will need to read the documentation of your serial device to find commands that it will receive. To write to the serial port, I have created a "Start" button on the form. I have added code to its Click_Event:
The SCL frequency may vary a lot with the processor and disk usage of the computer.I don't recommand a such solution if a lot of data have to be transmitted. But the RS232 to I2C circuit is cheap and perfect to command slows devices as LED, lamps, motors, or readslow variation of temperature and so on.
Sometimes we require to communicate with an external device like a printer, microcontroller board or any serial device using the serial port of a windows machine. There is a lot of serial application available like Hercules, HyperTerminal, Docklight, ..etc.
In this blog post, we will learn serial port programming using the Win32 API. In Windows, serial port programming is very easy, MSDN provide all the required win32 API information which require for the serial port programming.
In windows, the serial device will display in com port section of device manager with name as COM1, COM2, COM3, COM4.. etc. Generally, COM1 and COM2 refer to the hardware serial ports present in the PC and another com port number is export when any serial device or USB to serial device attached to PC. It also possible that com id could be virtual ( for example static virtual com port).
In the below console application, I am using the win32 API to open the com port and sending the data to the open COM port. See the below video where I have downloaded the Arduino code in the Arduino board and communicating with this board using the console application.
Serial communication is the most common low-level protocol for communicating between two or more devices. Normally, one device is a computer, while the other device can be a modem, a printer, Arduino hardware, another computer, or a scientific instrument such as an oscilloscope or a function generator. For many serial port applications, you can communicate with your instrument without detailed knowledge of how the serial port works. Communication through a serial port is established with a serialport object, which you create in the MATLAB workspace. For information about creating a serialport object, see Create Serial Port Object.
OK, now we can start doing real communication. However, it is very important that you have prior knowledge of what kind of data the connected device is expecting. and you will need to process their response as well to understand what they are saying. For this, you will need the corresponding firmware API command lists. Here, I will give a simple prototype of how the send/receive data workflow will be:
You mean you want to write driver software for serial port accessible devices? If so, you must need to have the command set that the device accepts and what it replies in response. If you got that, you can even use this article to send and receive data.
Hello Md Ali Ahsan Ranamy problem is that i trying to get input from Weight machine ( Connection= USB, Company=DYMO Endicia Postage Technology,Item No=ES-7500UBLK) in web application in asp.net.Please give me any code if you have for this.Thanks in advance
hi . i m working with rfeid serial module , i want to use with it .net apllication i want to know that which approach is better ?1 : to open serial port when software is running at startup2: or open serial port when needed after communication close itplease reply .