C# Serial Port Read - Get COBS coded messages with different lenght - c#

so im new in C# Programming. I have programmed a C# Forms Application in Visual Studio to communicate to/initialze a device over the Serial Port. The communication between the device is COBS coded, so there are no 0x00 bytes except on the end of each message. The messages sent and received have different length.
My problem is at the moment, that the Messages I receive are not complete or start at the middle of a message, so i cannot trigger sent messages on a specific value in the received messages. You can determine end of a message with received 0x00 (0x00 means end of message in COBS coded data)
So what i need is something to handle the complete message and put it in a byte array to analyze i.e. byte[11] for a specific value.
Here is what ive done so far:
private bool b_portopen = false;
private byte[] b_rcv_buffer = new byte[256];
private void button1_Click(object sender, EventArgs e) {
//InitTimer();
if (b_portopen == false)
{
serialPort1.PortName = comboBox1.SelectedItem.ToString();
serialPort1.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);
serialPort1.Open();
b_portopen = true;
button1.Text = "Close";
button2.Enabled = true;
Console.WriteLine("Serial Port Opened");
}
else if (b_portopen == true)
{
serialPort1.Close();
b_portopen = false;
button1.Text = "Open";
button2.Enabled = false;
Console.WriteLine("Serial Port Closed");
}
}
private async void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
{
serialPort1.Read(b_rcv_buffer, 0, 256);
//serialPort1.Read(b_rcv_buffer1, 11, 2);
richTextBox1_receive.Invoke(new Action(() =>
{
richTextBox1_receive.AppendText(BitConverter.ToString(b_rcv_buffer) + "\n");
richTextBox1_receive.ScrollToCaret();
}));
switch (b_rcv_buffer[10])
{
case b_state_startup:
do something
case b_state_be_start_conf:
do something
case b_state_keepalive_conf:
do something
case b_state_unprepare_conf:
do something
case b_state_prepare_conf:
do something
}
}

So, i found a solution with using ConcurrentQueue:
ConcurrentQueue<byte> b_rcv_buffer = new ConcurrentQueue<byte>();
private Timer timer2;
public void InitTimer()
{
timer2 = new System.Windows.Forms.Timer();
timer2.Tick += new EventHandler(timer2_Tick);
timer2.Interval = 1; // in miliseconds
timer2.Start();
}
private async void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
{
int bytes = serialPort1.BytesToRead;
byte[] buf = new byte[bytes];
serialPort1.Read(buf, 0, serialPort1.BytesToRead);
for(int i = 0; i < buf.Length; i++)
{
b_rcv_buffer.Enqueue(buf[i]); //Enqueue every received Byte in Concurrentqueue
}
}
private async void timer2_Tick(object sender, EventArgs e)
{
if (b_rcv_buffer.Contains<byte>(0x00))
{
byte[] array = b_rcv_buffer.ToArray();
richTextBox1_receive.Invoke(new Action(() =>
{
richTextBox1_receive.AppendText(BitConverter.ToString(array) + "\n");
//richTextBox1_receive.ScrollToCaret();
}));
byte ignored;
while (b_rcv_buffer.TryDequeue(out ignored));
}

Related

How to receive data from a server?

I'm coding a chat application with C# Windows Froms. My problem is that, my server can send messages to each connected client but only a client that sent a message can receive a response. I tried to create a function like ReceiveLoop() with an infinite loop inside or add a timer and call Receive() function for each tick but both were unsuccessful due to the app's crash.
How to get the data in real time? I attach my client's app code.
public partial class Form1 : Form
{
private string name;
private Socket _clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
private void Namebt_Click(object sender, EventArgs e)
{
if (!Test(Nametb.Text)) Nametb.Text = "Nie wpisano nazwy!";
else
{
name = Nametb.Text;
Nametb.Clear();
Nametb.Enabled = false;
Namebt.Enabled = false;
Messageslb.Enabled = true;
timer1.Start();
LoopConnect();
}
}
private void LoopConnect()
{
int attempts = 0;
while (!_clientSocket.Connected)
{
try
{
attempts++;
_clientSocket.Connect(IPAddress.Loopback, 100);
}
catch (SocketException)
{
Messageslb.Items.Clear();
Messageslb.Items.Add("Connection attempts: " + attempts.ToString());
Messageslb.Refresh();
}
}
Messageslb.Items.Add("Connected!");
Messageslb.Refresh();
Messagetb.Enabled = true;
Sendbt.Enabled = true;
}
private bool Test(string text)
{
if (text != "") return true;
return false;
}
private void Sendbt_Click(object sender, EventArgs e)
{
if (!Test(Messagetb.Text)) Messagetb.Text = "Nie wpisano zadnej wiadomosci!";
else
{
Send();
}
}
private void Receive()
{
if(_clientSocket.ReceiveBufferSize > 0)
{
byte[] receivedBuffer = new byte[1024];
int rec = _clientSocket.Receive(receivedBuffer);
byte[] data = new byte[rec];
Array.Copy(receivedBuffer, data, rec);
Messageslb.Items.Add(Encoding.ASCII.GetString(data));
}
}
private void Send()
{
string message = "[" + name + "]: " + Messagetb.Text;
Messagetb.Clear();
byte[] buffer = Encoding.ASCII.GetBytes(message);
_clientSocket.Send(buffer);
Receive();
}
private void Nametb_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Return) Namebt_Click(sender, e);
}
private void Messagetb_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Return) Sendbt_Click(sender, e);
}
private void timer1_Tick(object sender, EventArgs e)
{
Receive();
}
}
You need to run the receive method on a separate task.
_clientSocket.Receive(receivedBuffer);
should be:
private Task _receiving;
private void Receive()
{
if(_clientSocket.ReceiveBufferSize > 0)
{
if(_receiving == null || _receiving.IsCompleted)
_receiving = Task.Run(() =>
{
byte[] receivedBuffer = new byte[1024];
int rec = _clientSocket.Receive(receivedBuffer);
byte[] data = new byte[rec];
Array.Copy(receivedBuffer, data, rec);
Messageslb.Items.Add(Encoding.ASCII.GetString(data));
});
}
}
Otherwise clientSocket.Receive will hang your program.
You will want to make sure Messageslb is thread safe though, that will take further research.
If you're looking for real time communication look into RTC Client for C# https://msdn.microsoft.com/en-us/library/ms946701.aspx. Otherwise I would highly recommend Socket.IO since it is truly simple to use and set up with extremely fast rtc! https://socket.io/get-started/chat

Scoreboard data transfer Serial Port c#

There's some outdated software that's used to control the scoreboard at my local athletics track and I've been tasked with creating a new advanced one. However, I cannot seem to get the scoreboard to do what I ask it to do.
I've installed the original software to the my laptop and it works fine, however, when I run my test software that sends data to the board through the serial port, it isn't doing what I want.
I have the "Scoreboard Data Protocol" supplied by the manufacturer and I've been following this. I will supply the code to my test program that I've been using to see if I can get it to work and I will also supply the Data Protocol.
In the text box, I type 010D0201SPAIN and 003C630 and send it to the board and this doesn't work.
public partial class Form1 : Form
{
private SerialPort m_port;
public Form1()
{
InitializeComponent();
m_list.Items.AddRange(SerialPort.GetPortNames()); // Adds ports to combobox
m_port = new SerialPort();
m_port.BaudRate = 9600;
m_port.DataBits = 8;
m_port.Parity = Parity.Even;
m_port.StopBits = StopBits.One;
//m_port.Handshake = Handshake.None;
m_port.Encoding = new ASCIIEncoding();
m_port.RtsEnable = true;
m_port.DtrEnable = true;
m_port.ReceivedBytesThreshold = 1;
m_port.DataReceived += DataReceivedEvent;
}
private void button1_Click(object sender, EventArgs e)
{
m_port.Close();
m_port.PortName = (string)m_list.SelectedItem;
try
{
m_port.Open();
m_sendbutton.Enabled = true;
button2.Enabled = true;
}catch(UnauthorizedAccessException ex)
{
MessageBox.Show(ex.Message);
}
}
private void m_sendbutton_Click(object sender, EventArgs e)
{
m_port.Write(m_textbox.Text);
}
private void DataReceivedEvent(object sender, SerialDataReceivedEventArgs args)
{
Invoke(new EventHandler(DoUpdate));
}
private void DoUpdate(object s, EventArgs e)
{
label1.Text += m_port.ReadLine();
}
private void button2_Click(object sender, EventArgs e)
{
byte[] r_bytes = Encoding.ASCII.GetBytes(m_textbox.Text);
m_port.Write(r_bytes, 0, r_bytes.Length);
}
}
}
Scoreboard Data Protocol
Code: https://hastebin.com/epirobuduv.cs
Here's how to add STX and ETX around your message, in a byte array.
private void button2_Click(object sender, EventArgs e)
{
var msg = Encoding.ASCII.GetBytes(m_textbox.Text).ToList();
msg.Insert(0, 0x02); // STX at the start
msg.Add(0x03); // ETX at the end
m_port.Write(msg.ToArray(), 0, msg.Count);
}

Receive data from weighing scale CAS CL5200

Need help with CAS CL5200 scale.
i have already seen all the posts regarding this problem , but none of them are working regarding CAS CL5200 scale- connected with USB cable that creates a virtual com port (COM41)
here are the steps i followed -
To test the communication, I installed CL-Works (scales software for some functions) --> working.
Installed Free Device Monitoring Studio to see all the connection params.
Tested with hyperterminal --> not working
Free Device Monitoring Studio reports that "W" is written to com port but nothing returns.
The code here is what I found on other related post, tested it with byte[] and string, either way the code writes on COM41 "W" but there is nothing to read.
Code:
public partial class Form1 : Form
{
private const int BaudRate = 19200; // BaudRate Constant
private SerialPort _serialPort;
private void button1_Click_1(object sender, EventArgs e)
{
if (_serialPort != null && _serialPort.IsOpen)
_serialPort.Close();
if (_serialPort != null)
_serialPort.Dispose();
_serialPort = new SerialPort("COM41", BaudRate, Parity.None, 8, StopBits.One); // Creates new SerialPort using the name selected in the combobox
_serialPort.Handshake = Handshake.None;
// _serialPort.DataReceived += SerialPortOnDataReceived; // this event happens everytime when new data is received by the ComPort
_serialPort.DataReceived += new SerialDataReceivedEventHandler(_serialPort_DataReceived);
_serialPort.RtsEnable = true;
_serialPort.DtrEnable = true;
_serialPort.Open();
textBox1.Text = "Listening on " + _serialPort.PortName + "...\r\n";
// byte[] towrite = GetBytes("W"); // get the weight from scale wiyh "W" as byte[]
// _serialPort.Write(towrite,0,1);
_serialPort.WriteLine("W");
}
private delegate void Closure();
void _serialPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
if (InvokeRequired) // makes sure the function is invoked to work properly in the UI-Thread
BeginInvoke(new Closure(() => { _serialPort_DataReceived(sender, e); })); //<-- Function invokes itself
else
while (_serialPort.BytesToRead > 0) //<-- repeats until the In-Buffer is empty
{
//textBox1.Text += string.Format("{0:X2} ", _serialPort.ReadByte());
textBox1.Text += _serialPort.ReadExisting();
//<-- bytewise adds inbuffer to textbox
}
}
private byte[] GetBytes(string str)
{
byte[] bytes = new byte[str.Length * sizeof(char)];
Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);
return bytes;
}
}
If you can't see the data in the hyperterminal, you can't see it in the code you wrote. See it there first. then try this
private void serialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
Get_Data(serialPort1.ReadLine().ToString());
}
private void Get_Data(string Result_Data)
{
Application.DoEvents();
if (!InvokeRequired)
{
try
{
double dNew = Convert.ToDouble(Result_Data) / 100;
lbl_weight.Text = dNew.ToString("N2");
}
catch (Exception err)
{
MessageBox.Show(err.ToString());
}
}
else { Invoke((MethodInvoker)(() => Get_Data(Result_Data))); }
Application.DoEvents();
}
public void Connection_Start()
{
string comport = "COM1";
serialPort1.DataReceived += new
SerialDataReceivedEventHandler(serialPort1_DataReceived);
serialPort1.PortName = comport;
serialPort1.BaudRate = 9600;
serialPort1.Parity = Parity.None;
serialPort1.DataBits = 8;
serialPort1.StopBits = StopBits.One;
serialPort1.DtrEnable = true;
serialPort1.Open();
}

C# serial connection not working

I am trying to send ASCII caracters to a VideoJet Excel 170i printer, via a RS-232 cable (Serial)
When I am using the test program, i have no problem getting a response from the printer, i can change the status of the printer.
This is the code i've made
public partial class Form1 : Form
{
private SerialPort port = new SerialPort("COM1");
private delegate void SetTextDeleg(string data);
public Form1()
{
InitializeComponent();
}
private void addtoText(string text)
{
this.richTextBox1.Text = this.richTextBox1.Text + "\n" + text;
}
private void Form1_Load(object sender, EventArgs e)
{
try
{
port.BaudRate = 9600;
port.Parity = Parity.None;
port.StopBits = StopBits.One;
port.DataBits = 8;
port.Handshake = Handshake.None;
port.ReadTimeout = 2000;
port.WriteTimeout = 500;
port.DtrEnable = true;
port.RtsEnable = true;
port.Open();
port.DataReceived += DataReceivedHandler;
addtoText("Port is ready");
}
catch (Exception ex)
{
//Console.WriteLine("Error opening my port: {0}", ex.Message);
addtoText("Error opening my port: {0}" + ex.Message);
}
}
public void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
{
SerialPort sp = (SerialPort)sender;
System.Threading.Thread.Sleep(500);
string indata = sp.ReadExisting();
this.BeginInvoke(new SetTextDeleg(DisplayToUI), new object[] { indata });
}
private void DisplayToUI(string displayData)
{
addtoText(displayData);
}
private void button1_Click(object sender, EventArgs e)
{
port.Write(tbxAscii.Text);
}
private void Form1_Leave(object sender, EventArgs e)
{
port.Close();
}
}
I need to sent ASCII caracters to the printer, like
[1B][01][09]
To turn the printer to Print Mode.
The printer is supposed to respond, i get no response, and the printer doesn't change its status.
I have a program made to test the serial connection made by the printer, and i can see that all the settings are OK (Baud rate, Parity... port), and indeed on port COM1.
So i think that my port.write is not sending any info to the printer... or maybe i'm sending corrup info and i'm not reading the response of the printer.
are you sure that you want to send [1B][01][09] or do you want to send that byte sequence 0x1b,0x01,0x09
just to see if this works, send the following in you click handler
private void button1_Click(object sender, EventArgs e)
{
var bytes = new byte[] { 0x1b, 0x01, 0x09 };
port.Write(bytes, 0, bytes.Length);
port.Flush(); // make sure everything is written
}
reading has to be changed, to handle bytes
SerialPort sp = (SerialPort)sender;
System.Threading.Thread.Sleep(500);
var available = sp.BytesToRead; // check how many bytes are ready to be read
if (available < 1)
return;
var buffer = new byte[available];
sp.Read(buffer, 0, available);
var indata = BitConverter.ToString(buffer); // convert bytes to a hex representation
this.BeginInvoke(new SetTextDeleg(DisplayToUI), new object[] { indata });

SerialPort.BaseStream.BeginWrite & BeginRead questions

I'm having some issues trying to figure out Async communication on a serialport object and was hoping to get some help. I'm still learning Async stuff so be gentle:)
I basically need to make sure that the buffer isn't full prior to writing to the serial port and also all data has been read before any more data gets written to avoid packet collision. Unfortunately the microcontroller that I am writing to does not have any handshaking or CTSEnabled so I have to mimic it in code.
public partial class Form2 : Form
{
System.IO.Ports.SerialPort port = new System.IO.Ports.SerialPort();
System.Timers.Timer tmrPolling = new System.Timers.Timer(200);
static byte [] inputPacket = new byte[2] { (byte)255, (byte)0 }; // Byte to send to SerialPort when input polling timer is activated.
AsyncCallback callback;
IAsyncResult result;
Form2()
{
InitializeComponent();
port.PortName = "COM9";
port.BaudRate = 38400;
port.DataBits = 8;
port.StopBits = System.IO.Ports.StopBits.One;
port.Parity = System.IO.Ports.Parity.None;
port.ReadTimeout = 1;
port.ReceivedBytesThreshold = 5;
port.DataReceived += new System.IO.Ports.SerialDataReceivedEventHandler(port_DataReceived);
callback = new AsyncCallback(ReadComplete);
port.ReadBufferSize = (byte)60;
port.WriteBufferSize = (byte)60;
port.Open();
tmrPolling.Elapsed += new System.Timers.ElapsedEventHandler(tmrPolling_Elapsed);
}
void WritePacket(byte[] packet)
{
result = port.BaseStream.BeginWrite(packet, 0, packet.Count(), callback, port); // writes the input packet to the SerialPort - needed to read the IO values
}
void ReadComplete(IAsyncResult result)
{
}
void tmrPolling_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
WritePacket(inputPacket); // writes the input packet to the SerialPort - needed to read the IO values
}
void port_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
port.BaseStream.EndWrite(result);
// Reads the data coming in from the serial port and calls the thread safe delegate to update the values on the form.
byte [] received = new byte[port.BytesToRead];
result = port.BaseStream.BeginRead(received, 0, received.Count(), callback, port);
port.BaseStream.EndRead(result);
}
private void UpdateValues()
{
byte[] b = new byte[] { (byte)255, (byte)6, (byte)hsbPan.Value, (byte)vsbTilt.Value, (byte)0,
(byte)0, (byte)0, (byte)0, (byte)13, (byte)10 };
WritePacket(b);
}
private void chkEnablePolling_CheckedChanged(object sender, EventArgs e)
{
tmrPolling.Enabled = chkEnablePolling.Checked;
test.Enabled = chkEnablePolling.Checked;
vsbInputInterval.Enabled = chkEnablePolling.Checked;
vsbInputInterval.Value = Convert.ToInt32(tmrPolling.Interval);
txtInputInterval.Enabled = chkEnablePolling.Checked;
txtInputInterval.Text = ((float)tmrPolling.Interval / ( float)1000).ToString() + " sec";
}
private void vsbInputInterval_Scroll(object sender, ScrollEventArgs e)
{
// adjusts the tick frequency of the Timer for input polling.
txtInputInterval.Text = ((float)tmrPolling.Interval / (float)1000).ToString() + " sec";
tmrPolling.Interval = vsbInputInterval.Value;
}
private void vsbTilt_Scroll(object sender, ScrollEventArgs e)
{
UpdateValues();
}
private void hsbPan_Scroll(object sender, ScrollEventArgs e)
{
UpdateValues();
}
}

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