serial port and data sequencing problem...?

[rahvyn6]

I'm not sure I understand what you are asking. You should be able to call a function from with the data_recieved() function. Like this: private void seriport_DataReceived(object sender, SerialDataReceivedEventArgs e) { // This method will be called when there is data waiting in the port's buffer string[] data; data = comport.ReadLine().Split(System.Convert.ToChar(":")); FunctionCall(); }

[Mir_As]

i mean that must i break this thread?i tried to write serial data in serialport_datareceived();function but i didnt do it. must i use some "invoke" code and "break" like break codes?

[rahvyn6]

Can you post the portion of the code you are having problems with?

[Mir_As]

i ll try:) did u write anything in this function?i mean did u try to write this data do textboxes in serialport_datareceived(..)?i tried but i didnt do it:)

[rahvyn6]

What errors are you getting? Are you simply trying to set the .Text value of a textbox?

[Mir_As]

yes.i cant remember now. now i try "readline" :).but my variables come very frequently.so must i clear "string[] data" ?my data will come every milisecond

[rahvyn6]

Yes, once you parse the recieved data, you can clear the array that holds it. Another option would be to close the port until you need it opened again. To clear the array, I think this should work: Array.Clear(data, 0, data.Length);

[Mir_As]

"cause of thread output or an application I/O prossesing was canceled" i get this warning:)i didnt get serial datas:) i think i must write invoke but how:)

[rahvyn6]

Do you get any errors when you open the port? Also, can you post the code within the data_recieved event handler?

[Mir_As]

string[] data; private void serialPort1_DataReceived(object sender,System.IO.Ports.SerialDataReceivedEventArgs e) { //problemhere//data=serialPort1.ReadLine().Split(System.Convert.ToChar(":")); serialPort1.Close(); write(); }

[rahvyn6]

Hmm, how are you opening the port? I can run the line where you are getting the error. Here is how I open mine: try { if (comport.IsOpen) comport.Close(); else { // Set the port's settings comport.BaudRate = int.Parse(Settings.Default.BaudRate.ToString()); comport.DataBits = int.Parse(Settings.Default.DataBits.ToString()); comport.StopBits = (StopBits)Settings.Default.StopBits; comport.Parity = (Parity)Settings.Default.Parity; comport.PortName = Settings.Default.PortName.ToString(); // Open the port try { comport.Open(); } catch { } } } catch (Exception ex) { //no com port may be present log.Write("ERROR: " + ex.Message, "InitializePort"); }

[Mir_As]

soon before i see blue screen on DOS:) it must be dangerous error?.now i ll try your code.

[Mir_As]

what is the "log" in your programme? log.write(.....) i mean this log. i try to write:)

[rahvyn6]

You can take that out, its a class I wrote for logging errors.

[Mir_As]

my friend my computer will die soon:)second time my computer closed itself. i just want to sequence my 6 datas.

[rahvyn6]

Im not sure what else to tell you without seeing the code as a whole. What I have posted should work. Com ports are pretty easy to work with, just make sure its opened correctly, then read the data and do what you need to do with it.

[Mir_As]

i have done it many times.my problem is that: i have a simulation project in wpf.so my serial datas will will simulate my robot arm s axises.for example:i send from microcontrolor to computer this: for(;;) { delay_ms(1); putc(value1); putc(':'); putc(value2); putc(':'); putc(value3); putc(':') putc(value4); putc(':'); putc(value5); putc(':'); putc(value6); } so i must get datas like this: "value1" for "axis 1","value2" for "axis2" .... now could i explain my problem?

[rahvyn6]

Ok, try concatinating all values into one string, then sending that string to the port all at once. putc(value1 & ":" & value2 & ":" & value3 & ":" & value4 & ":" & value5 & ":" & value6); Not sure what language you are using to send the information, so may need a different concatenation value. Then, when you recieve the data, you will get the whole string at once, and the Split() command will split all the values so data[0] will hold value1, data[1] will hold value2 and so on.

[Luc Pattyn]

Sorry, but I doubt the entire concept of your project. 1) Reality check: you want to send 6 bytes of data at 9600 Baud ? with 1 start bit, 1 stop bit, no parity bit, a byte takes 10 bit times (a bit time is 1 second divided by the baudrate), that leads to a maximum of 960 bytes per second (lets call this 1000 bytes per second, or 1 msec/byte for easier calculations). Assuming you could send just 6 bytes (i.e. no overhead) you will need almost 6 msec to transfer the amount of data you want to transfer every msec !?!? 2) if 9600 Baud is the maximum your serial port (PC or target) can support, you are stuck. You need more bandwidth, i.e. a higher baudrate, or a different interface hardware all together; alternatively (and preferably, assuming data is not changing much) you should select some setup with buffering+compression at the producer side (target), and buffering+decompression at the consumer side (PC). 3) you dont need separation characters between the six bytes, they serve no purpose; you do need something that shows which byte is the first of a series of six. Lets assume you use 7 bytes: 1 special character indicating "start of data", followed by 6 data bytes. Your "start of data" value might also occur in one of the data bytes, and hence you could have a case of mistaken synchronization, but if you test for that and react properly, it will solve itself after a while (unless you are really unlucky; to understand assume 5 of the 6 values you need to send happen to also have that special value: how then can you tell to what channel belongs the one byte that differs ???) 4) It will not be obvious to get the PC listen to the serial data in real-time; PCs are not good in real-time stuff, they tend to do a whole lot of things, some in foreground, some in background, and typically fast enough to satisfy the human user (who tolerates delays of 10 or 100 msec, and occasionally a full second). If you need better, you must work with "real-time" priorities, which easily will ruin the behavior of all other processes unless you get everything correct, not a simple job. 5) The normal way to connect a device (such as a robot arm) to a computer (such as a PC) is by having a smarter target that executes intelligent commands, and reports higher-level results (things like: rotate 20 degrees per second for the next 3 seconds; and "rotation' done; new position=...". At that pace, you can easily have the PC follow the target. Compare this with a printer: you send one byte to instruct

[Ed Poore]

If your micro is sending indivdual characters then in most cases the DataReceived event will be fired the number of times the characters are sent, i.e. you're trying to send 6 characters but by using 6 individual putcs it will fire off 6 DataReceived events.  The best way would be to have a buffer to do something like this:

List<byte> buffer = new List<byte>();
private void serialPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    buffer.Add(serialPort.ReadByte());
    if (buffer.Length == 6)
    {
       // Call your function here
       YourFunctionCall(buffer.ToArray());
       // Clear the buffer
       buffer.Clear();
    }
}

The problem you mentioned in the other thread about Invoke is basically because Windows is using a different thread to receive data from the SerialPort, this is the one which is the owner of the DataReceived event.  If you want to update for example some textboxes with teh values you receive you will have to do something like this:

private delegate void UpdateTextBoxes(byte[] values);
private void YourFunctionCall(byte[] values)
{
    this.Invoke(new UpdateTextBoxes(this.UpdateTextBoxes));
}
privaet vodi UpdateTextBoxes(byte[] values)
{
    this.txt1.Text = values[0].ToString();
    this.txt2.Text = values[1].ToString();
    // ...
}

You might want to take a look at my article[^] which looks into this problem.

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