I have a driver for the device and I already have it integrated into an application.
It is a Human Input Device with buttons.
Controlling the device is not the issue nor is receiving button presses.
I want to retrieve the actual data that is being sent from the device to the computer and from the computer to the device.
I have seen a lot of hardware approaches but not any software approaches(that work right).
I'm working on a windows forms application (.NET 4.0).My form contains a 'Fast Line' chart using the Microsoft chart control included in VS2010.The chart gets filled with about 20,000 datapoints.My application then starts receiving market data from a server via DDE (Dynamic Data Exchange) in real-time and adds it the chart.
View 5 RepliesI have to send a sequence of video frames over UDP as fast and real-time as possible and while I got the basics working, I am running into all sorts of difficulties. Some of my goals:Data will normally be sent over dial-up (hence UDP instead of TCP), but also needs to support fast Ethernet.It's OK to occasionally drop frames (hence UDP instead of TCP).Need low latency. The frame the remote receives should be one that was recently sent (no more than a few frames waiting in buffers).I need to be able to detect the effective bandwidth so that I can compress the frames more or less to keep frame rate up.I break up frame data into one or more datagrams of about 500 bytes and each has a sequence number and other info. The receiver reassembles the entire frame and detects if any datagrams are missing.If the receiver detects more than a certain percentage of dropped frames (e.g. 50% over the last 10 frames), I send a TCP message to the sender to slow down by 50%. Sender than slowly increases speed by 5% each subsequent frame.Using System.Net.Sockets.UdpClient to send and receive the data.I have a separate TCP channel used for control messages back to sender.My main difficulty right now is detecting the effective bandwidth and dealing with latency, especially over dial-up (max ~4,000 bytes/sec). For example, if I try to send 100,000 bytes/second using TcpClient.Send() they ALL seem to arrive (no dropped datagrams) but with large latency by the time last datagram arrives. I think the TcpClient.Send() function is blocking until the buffer is able to send which messes up my current algorithm.
Can anybody point me to any sources of information for how to:Detect actual bandwidth over UDP.A better algorithm for dynamically adjusting bandwidth to suit the available pipe.Send data smoothly at the desired bandwidth.A way to detect and keep latency down to a minimum.I have been spinning my wheels over the last week and every time I solve one problem it seems another rears up is head.
are there any ways that i can extract my data from database and display it into my listbox in real-time? which means that whatever is updated in my database must immediately be inserted into the listbox without the need of refreshing or pressing any buttons. Immediate display.
View 3 Repliesmethods/procedures for sending real time data from a VB.net app to a web server (asp.net) for real time display. My question relates to the best method to send the data from the desktop app and the best way to receive and handle the data on the server. I'm not asking for sample code, just some idea of what methods to research. I am currently using a text file upload method but I'm sure there is a more efficient way of achieving this.
View 2 RepliesI have been trying to find and/or think up a way for data to automatically update a data table.I have a log that shows all the customers that came in today with various information. There could be twenty or thirty employees adding to this log or updating or doing things with that customer. This information is in a Data Table on a ASPX page in Visual Studio 2010 that the code is binded in the aspx.vb page that is calling a page in my APP_CODE database file that calls a query in my Database to get the information.My question is could someones actions on a different computer make my computer refresh or to re-bind that data.I have thought of some kind of timer/counter maybe that looks to see if the count of the log is different.
View 2 RepliesI'm using EF version 4.1, and would like to have the data from the database in realtime, i.e. if you open the application it detects if there is new data in the database, and update the above it! is It possible to do this? I am using EF 4.1 code first time
View 1 Repliesi have a program that function as a DAQ System.i have input channel to gather information from sensors. The reading of each sensor such as voltage, current and temperature are displayed in the textbook. As we all know, DAQ system is involve taking data real-time measurement.My problem is:
1. how to update each row automatically as time goes on. the value in the textbook is updated by each second.Below figure shows how the excel can be written automatically row by row, as time ticking for a sec. this update will stop as the timer stop.
Basically I have a program that receives real time data from microcontroller and displays it in a text box. What I would now like to do is to store the values received into a table that can be viewed when the receive program finishes. However I still want the values displayed as they are received in addition to being stored in a table of some sort.
View 3 RepliesI'm having a bit of an issue receiving a stream of serial data and displaying the data real-time in my GUI. I am fairly new to VB.Here's what I'm trying to achieve: I have an I2C device (bank of LED's) connected to my Arduino. Using the VB.NET (2010) GUI I request which LED I want on (via buttons) and the I2C device then sends a reply confirming which LED actually turned on (basic feedback). Ok, sounds great right? Here's where I get issues. Well when I try to read the serial data sent to VB and display the real-time stream on the GUI, a) I get a bit of a mess as an output (values are ok, just spewn across GUI) and b) when I select a new LED to turn on, the GUI data does not refresh to this change. The stream being sent from the Arduino is ok, I looked at the data in a serial monitor.
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I've use VB net to create a application that can download the real-time data from a device for every second. Now I want to upload the data to a website in real time. (So some who is far away, can also check the data through the website)
View 3 RepliesHBasically I will have two forms. Form1 will control form2 which is the media display. Form2 will give back the media status and info back to form1 in someway. I was thinking of creating properties in form2 and having form1 polling these values to display the elapse run time etc... ideally i wish to have form2 somehow send events back with data when it values gets updated.
View 1 RepliesI am working on a project that is able to display real time data from sensors from micro-controller. I am able to do so by sending the data through the serial port and then use vb 2005 to show the data. However, I want to save those data from vb 2005 to excel. How am I able to do it ? I am able to use vb to insert data to excel step by step, cell by cell using the following codes.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim oExcel As Object
Dim oBook As Object
Dim oSheet As Object
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Lets say TextBox1.Text and TextBox2.Text is my real time data. How do I save it to the excel sheet displaying the data in cell A2, A3, A4 when the time goes by. Eg. If I want to save TextBox1.Text to excel it would be, the data in the 1st seconds in cell A2, data in the 2nd seconds in A3, 3rd seconds A4, 4th seconds in A5, A6 and so on...
On VB.NET 2005 and 2008, if you were debugging you could roll over the variable you set as an array and a little "+" would pop up next to the array variable and you could click it and see all of the data loaded into the array.
View 3 Repliesconnected to my Arduino. Using the VB.NET (2010) GUI I request which LED I want on (via buttons) and the I2C device then sends a reply confirming which LED actually turned on (basic feedback). Ok, sounds great right? Here's where I get issues. Well when I try to read the serial data sent to VB and display the real-time stream on the GUI, a) I get a bit of a mess as an output (values are ok, just spewn across GUI) and b) when I select a new LED to turn on, the GUI data does not refresh to this change. The stream being sent from the Arduino is ok, I looked at the data in a serial monitor.
Public Class Form1
Dim ticktock As Integer
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
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I am busy with a VB2008 EXPRESS program that reads is data via a network cable. Saving the data on the same computer as my program is not a problem, but I must also make this data available to other users in the network and update their screens in real time. In other words I need a COPY of my running program on each networked computer when requested by the user in the network. I have looked at SQL, XML pages and inheritance. But I am confused, what is the best way???
View 13 RepliesI m into automation development of FMCG products using Micro-controllers. I get real time data Barcode 2D from TCP/IP connection. My task is to compare the result do some Computation with them and Store the incoming Barcode and results into a Excel sheet in a folder. I m successful with the basic working. Am currently working at slow speed of 1 barcode(22 char info) per second from the TCP/IP data (barcode scanner). Now, comes the real issue. I need to process atleast 5 barcodes per sec ( <200ms per process). I m partially successful with 3 Barcode per second(300 ms per process). so, thats like 300ms per processing. I need to achieve less than 200ms for entire processing. I have used threads and timers. but I m unable to achieve. Seems like storing in Excel takes more than 250ms. Since i come from micro controllers background 1msec is a lotta time to process for me. I m not sure how much time does it take and trust me i find it difficult to guage the time here.
View 1 Replies- I'm working on a windows forms application (.NET 4.0). - My form contains a 'Fast Line' chart using the Microsoft chart control included in VS2010. - The chart gets filled with about 20,000 datapoints. - My application then starts receiving market data from a server via DDE (Dynamic Data Exchange) in real-time and adds it the chart.
Note: I have no control over the server and so I have to deal with DDE only even though it's an outdated technology. VS doesn't support DDE anymore and so I use the Ndde library which works like a charm.
Private Sub StartDDE()
'first we connect to the DDE server:
Dim client As DdeClient = New DdeClient("ServerApplication", "Bid")
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I have an Excel based algo-trading app that needs to take in lots of real-time data, and make trading decisions based on the calculations driven by the data. It is not one of those "read-only" stock ticker kinda spreadsheets.I created a COM object with VB.NET that runs in its own thread space which collects data from a socket, and when the data is read it raises an Event with data attached. In Excel VBA, the event handler parses the data, puts them to the right places on the spreadsheet to feed calculations (so far it sounds like a stock ticker app), and then, based on the results of the various calculations it does something.The problem is that when the user starts to click around the spreadsheet while there is large amount of data coming, the event handler's cell updating breaks apart. If the app is left alone without user action, it stands well. My frustration comes from not understanding what happens to the main thread when a user clicks around. Either the event handler blocks the user action, or the user action blocks the event handler (under which case I will put in some queuing facility). But I just don't see how user action can break the code (like causing VBA to stop executing)
View 9 RepliesI am having a little trouble receiving data via the serial port. I can send just fine. I am using Serial Port object.
Basically my data expected is in the form of: [0x43 0x35 0x64 0x35...] broken up into bytes. I tried using the SerialPort.Read() function but can't get it to work.
how to read data from a USB Port. I have a games joystick connected to a USB port on my computer and the joystick has 10 buttons which each when pressed sends some binary code into the computer via the USB port. I need to capture these button clicks and perform a different event for each button click.
View 8 Repliesi am a absolute beginner and i want to use vb to receive data from micro controller through serial port using rs232 standards, i found this code to receive the data serially, can any one tell me where should i paste this code, so that the data received will be displayed in message box.Private Sub DataReceived(ByVal sender As System.Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) HandlesSerialPort1.DataReceived
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After searching around I am still having issues with reading data from a serial port in VB.Net/VS2010. I know the Serial Port works, I can write to the port fine but when reading from it, nothing happens. I have only been programming for the last 3 weeks so am still trying to get my head around it all.
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how to write a code for reading serial port using vb.net with the combination of c#.
Note : (Its just reading data from the swipe).
Private Sub receive_data(ByVal sender As System.Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
Dim aBuffer(255) As Byte
Do While SerialPort1.BytesToRead > 0
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Basically, what I am trying to do is everytime I receive data from the serial port, I turn that data into an array (aBuffer) and I then call another sub using that info.The problem I'm having is that everytime I receive data, the array only fills up to the first 8 bytes! This isn't a problem when I receive smaller packets of 6 bytes but anything else gets chopped off.
What is really frustrating is that it seems quite fickle. I've read somewhere that this happens because the computer is handling the bytes received faster than they are being put in the buffer?? Not really sure but if I put a couple of breakpoints during debug, sometimes the array fills up correctly... Note the maximum size of any one incoming message would be 255 bytes.
This is an amateur radio project. I have a TNC (modem) that receives a digital stream (AX.25) from my radio. The TNC decodes the AX.25 frames and translates them to KISS frames (the protocol used between the TNC and the PC, see documentation here: [URL] It sends the data as HEX values.
What I'm looking for on the serial stream is the beginning of a data frame marked by 0xC0 0x00 and ending with 0xC0. Should be easy. Using serialport.readbyte() I should get binary data that I can convert to hex and look for the beginning of a data frame and then convert the subsequent data to ascii, as it will be text from a chat session.
Just to try it out and see the raw data coming from the port, I use teraterm or realterm and capture the data and it's a mix of junk (control frames and what not) and valid text. When I display the same data in a text box in VB I get data that look like this:
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Is there any other way to access a serial port using visual basic.net 2010? I followed the steps in this site, [URL] but I just got this output Open the serial port. Send the attention command to the modem. Wait for data to come back to the serial port... and stopped there. I can't get the Read the OK response data in the serial port. Close the serial port. And I was thinking, because it is very much easy to access serial port in vb6, so can I just use vb6 and then connect to visual basic.net? it is like a language inside a language.
View 3 RepliesCurrently, I am using a VB.NET to read data from serial port. when i open the serial port, the data is read and plotting the graphic at the same time
View 2 RepliesI am developing a Winforms application which read barcode from barcode scanner. It's an Human wedge scanner. This will work if I placed the cursor in any textbox or notepad. But i don't want like that. Reason is that it's cordless scanner. If some want to scan some thing in store they will move around, so there is possibility of screen saver coming or system gets locked if that happens the barcodes wont capture, but the user who is scanning the barcodes won't know this thing.
So i am reading the data using serial port communication and my scanner sending the data character by character, Not a whole string. so for that I wrote the following code. Thsi code will works if i am writing to any textbox. But it is not working if want to store it in any global string. Only first character is storing in the string. The below code is working perfectly fine. but if want to save the string in Global String variable instaed of textbox the only first character in the string is storing.
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Using 2008 VB.Net trying to do serial communications. I have a Scantron scanner I can send data to it, but I can not get read data back sent to my serial port. I have tried ReadLine, ReadByte, etc. but i'm not capturing anything, and I don't understand the DataReceived event. [Code]
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