Re: Read information from serial port in Mathlab format - C# Discussion Boards

Hi Richard,

Thanks for you reply. I stand that you told me and I going to try to explai better.

I downloaded a third software that read information from the serial com, for example (open serial port monitor or serial port monitor). This sofware when I open the conection to the com port, start to read the information and print this information in the monitor.

The information that is printed, is in 3 type of data:

1st format:

à.....L.±......
...(.ëà.....L>¡
.........V.ëà..
...L.¢.........
..ëà.....L.£...
........ëà.....
L.§...........ë

2nd format:

e0 08 15 03 00 04 4c 00 b1 01 00 06 00 00 00 
00 00 00 28 00 eb e0 09 15 03 00 04 4c 3e a1 
00 06 00 00 00 00 00 00 00 56 00 eb e0 0a 15 
03 00 04 4c 00 a2 00 00 00 00 00 00 00 00 00 
14 00 eb e0 0b 15 03 00 04 4c 00 a3 00 00 00 
00 00 00 00 00 00 16 00 eb e0 0c 15 03 00 04 
4c 00 a7 00 00 00 00 00 00 00 00 00 1b 00 eb

3th format:

This 3 format that i copied, are the same information, but in different condification.
Then replying you "question": yes ,the device sent the information in different codification.

Then I would like to know how can I do for get the information in byte format, (2nd format of my example), because this information is the information that I need read and then work whit this.

I hope explained better.
Thanks!!

Victor Gonzalez 2024 wrote:
the device sent the information in different codification.

No, the device sends some information as a stream of bytes. The three different outputs are just your code printing it in different forms.

But my original response stands: the device (whatever that is) is sending some binary data. But you still need to find out what format that data is in. That is not something anyone here can do for you, as we have no idea what that device is or what information it provides.

Hi,

1.
to read binary data use the method SerialPort.Read(Byte[], Int32, Int32)[^]

2.
I seldom use the DataReceived event as it is the source of a number of problems. I'd rather use a separate thread (or a BackGroundWorker) that periodically calls a Read method.

3.
I am puzzled by the fact that your second data format shows 15 bytes per line, not 16 as is usual.

4.
I noticed your data seems to have a periodicity of 21 bytes; when reformatted it looks like this:

e0 08 15 03 00 04 4c 00 b1 01 00 06 00 00 00 00 00 00 28 00 eb 
e0 09 15 03 00 04 4c 3e a1 00 06 00 00 00 00 00 00 00 56 00 eb 
e0 0a 15 03 00 04 4c 00 a2 00 00 00 00 00 00 00 00 00 14 00 eb
e0 0b 15 03 00 04 4c 00 a3 00 00 00 00 00 00 00 00 00 16 00 eb
e0 0c 15 03 00 04 4c 00 a7 00 00 00 00 00 00 00 00 00 1b 00 eb

Hope this helps.

Smile | :)

Luc Pattyn [My Articles]
The Windows 11 taskbar is a disgrace; a third-party add-on is needed to reverse the deterioration. I decline such a downgrade.

Hello all,

Yes periodicaly the data sended is 21 byte, but some times send 63 or 42 bytes.
I think that I found the solution and now I can red the data in decimanl and later I transofrm to "X".

Now I have another problem. When I start the program with out break point for debug, when I read the information i write to the screen, but this write not found, but if I put a break point and debug the progam, yes is writing the messages in the screen.

this is my code.

using System;
using System.IO.Ports;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Threading;

class PortDataReceived
{

    public static void Main()
    {

        SerialPort mySerialPort = new SerialPort("COM3");

        mySerialPort.BaudRate = 56000;
        mySerialPort.Parity = Parity.None;
        mySerialPort.StopBits = StopBits.One;
        mySerialPort.DataBits = 8;
        mySerialPort.Handshake = Handshake.None;
        mySerialPort.RtsEnable = true;

        mySerialPort.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);

        mySerialPort.Open();

        Console.WriteLine("Press any key to continue...");
        Console.WriteLine();
        Console.ReadKey();
        mySerialPort.Close();
    }

    private static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
    {

        
        SerialPort sp = (SerialPort)sender;

        
        int count = sp.BytesToRead;
        int count2 = 0;
        byte[] data = new byte[count];
        sp.Read(data, 0, data.Length);

        switch (data.Length)
        {

            case 63:
                Console.WriteLine("inicio carrera o  pause off");
                if (data[7].ToString("X").Equals("0") && data[8].ToString("X").Equals("A6"))
                {
                    Console.WriteLine("pause off");

                }
                else
                {
                    if (data[7].ToString("X").Equals("3E") && data[8].ToString("X").Equals("A1"))
                    {
                        Console.WriteLine("carrera go!");
                    }
                }
                break;
            
            case 21:
               //Console.WriteLine("vuelta o pause on o stop carrera manual");
                if (data[7].ToString("X").Equals("1B") && data[8].ToString("X").Equals("A9"))
                {
                    Console.WriteLine("contador vuelta y tiempo");
                    
                }
                else
                {
                    if (data[7].ToString("X").Equals("0") && data[8].ToString("X").Equals("A5"))
                    {
                        Console.WriteLine("pause on");
                    }
                    else
                    {
                        if (data[7].ToString("X").Equals("0") && data[8].ToString("X").Equals("A7"))
                            Console.WriteLine("stop forzado");
                    }
                }
                break ;


            case 42:
                Console.WriteLine(" fin carril");
                break ;
             
        }
        sp.DiscardInBuffer();

        /*string[] tablehex = new string[data.Length];
        
        for (int i = 0; i < count; i++)
        {
            tablehex[i] = data[i].;
           //tablehex[i] = hexvalue;

        }
                 
            //   Console.WriteLine(hexvalue.ToString());

            // Console.WriteLine(tablehex[count2].ToString());

        leertabla(tablehex);*/


    }

Suggestions:

1.
don't use ToString("X"), use ToString("X2") instead, so you always get two characters

2.
don't use ToString at all, you can simply replace

data[8].ToString("X").Equals("A9")

by

data[8]==0xA9

3. be warned, the DataReceived handler executes on a different thread and therefore cannot access GUI Controls directly. See for instance Invalid cross-thread operations[^]

Smile | :)

Luc Pattyn [My Articles]
The Windows 11 taskbar is a disgrace; a third-party add-on is needed to reverse the deterioration. I decline such a downgrade.

Hi Luc Thanks!!

About my problem of the printing data, I detected that is because the program "it's more speed" than the reading of the COM port. I fixed temporaly using a sleep of 5 seconds, but I have another question.

This hardware have some sensors (now 2) and send information from the COM port, and if I "active" these two sensors at the same time, I receive the data in the same time and it's to difficult manipulate the data.

Could you help me to try to find a solution about these topic?
Thanks!!

Your problem description is way too vague to get useful suggestions.

A couple of points:

1. why are you calling sp.DiscardInBuffer() ?
all the data that you get by executing Read operations is removed from the serial stream automatically, however if any data comes in while your handler is running will be thrown away, more specifically anything that comes in after sp.BytesToRead is not read and discarded.

2. you are ignoring the return value of sp.Read().
this method will not always return the number of bytes requested: when fewer are available, fewer will be returned!

3. you should not switch on the number of bytes read, as sp.BytesToRead may return just any value: it could be as low as 3, or as high as 300, all depending on what your peripheral is sending and how fast Windows is dealing with it.

4. you need to see the incoming data as chunks of one big stream, and provide code to detect the messages in that stream, then act on them. A serial port does not care about messages, it just sends bytes; so a DataReceived handler might get only half a message, or several messages, or ...

5. serial ports (and all interfaces to external devices) may temporarily fail, e.g. loose a few bytes; to get a reliable program your code must be capable of surviving such mishaps.

6. as I mentioned before, I would avoid DataReceived; collecting the incoming data, discovering the messages in the stream, and acting on them is way easier in a dedicated thread.

If you want someone to help, you need to provide lots of very specific information, such as:

1. description of the application. What is it about, is this a commercial peripheral (make & type), is the peripheral's software fixed?

2. is there a document that describes the protocol your peripheral is using on its serial port?

3. how often will a message be sent?

4. is there a master-slave relationship? i.e. send one command to get one response? that would be easy.
or is the peripheral free to send whatever and whenever it likes to do so?

etc.

All this info is needed to come up with a reliable approach.

Smile | :)

Luc Pattyn [My Articles]
The Windows 11 taskbar is a disgrace; a third-party add-on is needed to reverse the deterioration. I decline such a downgrade.

Hi Luc,

You are in the right, I'm wasn't clear and specific.

Hardware that I'm working:
DS-300 Electronic Racing Products.
photo of the product
specifications that I found

This hardware is an a scalextric race control. ( start, pause, stop, laps by slot, time of lap...). slot 1 have 1 sensor and slot 2 have another sensor, and when one of this sensors are actitated, the DS-300 sent the information since the COM PORT.

I checked and this is the information that send:

for example when I push start race I recevied this data:

e0	59	15	03	00	04	4c	3e	a1	00	06	00	00	00	00	00	00	00	a6	00	eb

e0	5f	15	03	00	04	4c	00	a2	00	00	00	00	00	00	00	00	00	69	00	eb

e0	60	15	03	00	04	4c	00	a3	00	00	00	00	00	00	00	00	00	6b	00	eb

63 bytes:

byte 8 and 9 indicates that I pushed start.
byte 10 and 11 indicates the counter time, for example 6 minuts of race.
byte 12 and 13 --> number of lap
byte 15,16,17,18 --> time spend of complete the lap.
byte 20 and 21 --> ever the same 00 eb.

this is an example of data for 1 lap.

e0	60	15	03	00	04	4c	00	a3	00	00	00	00	00	00	00	00	00	6b	00	eb

21 byte:

byte 8 and 9 indicates that sensor of lap.
byte 10 and 11 indicates the slot 1 or 2.
byte 12 and 13 --> number of lap
byte 15,16,17,18 --> time spend of complete the lap.
byte 20 and 21 --> ever the same 00 eb.

This is when I force the stop of the race:

e0	61	15	03	00	04	4c	00	a7	00	00	00	00	00	00	00	00	00	70	00	eb

21 byte:

byte 8 and 9 indicates that I pushed start.
byte 10 and 11 indicates the counter time, for example 6 minuts of race.
byte 12 and 13 --> number of lap
byte 15,16,17,18 --> time spend of complete the lap.
byte 20 and 21 --> ever the same 00 eb.

this is the pause on:

e0	6d	15	03	00	04	4c	00	a5	00	00	00	00	00	00	00	00	00	7a	00	eb

21 byte:

byte 8 and 9 indicates that I pushed pause on.
byte 20 and 21 --> ever the same 00 eb.

pause off:

e0	6e	15	03	00	04	4c	00	a6	00	00	00	00	00	00	00	00	00	7c	00	eb

e0	6f	15	03	00	04	4c	00	a2	00	00	00	00	00	00	00	00	00	79	00	eb

e0	70	15	03	00	04	4c	00	a3	00	00	00	00	00	00	00	00	00	7b	00	eb

63 bytes:
byte 8 and 9 indicates that I pushed pause off.
byte 20 and 21 --> ever the same 00 eb.

finish time and finish the race:

e0	02	15	03	00	04	4c	00	c0	00	00	00	00	00	01	00	00	00	2b	00	eb

eb	03	15	03	00	04	4c	00	a4	00	00	00	00	00	00	00	00	00	0f	00	eb

42 bytes

byte 8 and 9 indicates that the race is finished. 
byte 20 and 21 --> ever the same 00 eb.

What I would like:

I would like do a software that show all this data for the pilos are playing, because it's very important know how many laps are you having, the time of lap, etc...

I hope be clear and give you mor information.

Thanks in advance.
REgards

OK, so message traffic would be pretty low, and problems with the serial communication are rather unlikely. This is my first attempt (not tested!), it does NOT include communication recovery, that is: if something goes wrong (say a serial byte gets lost), it will continue to fail.

using System;
using System.IO.Ports;
using System.Threading;

namespace ConsoleApp1 {
	class PortDataReceived {
		private static SerialPort sp;
		private const string PORTNAME = "COM3";
		private const int MSGLEN = 21;

		public static void Main(string[] args) {
			sp = openPort();
			Console.WriteLine("Press any key to terminate...");
			Console.ReadKey();
			if (sp!=null) sp.Close();
		}

		private static SerialPort openPort() {
			try {
				SerialPort port = new SerialPort(PORTNAME);
				port.BaudRate = 56000;
				port.Parity = Parity.None;
				port.StopBits = StopBits.One;
				port.DataBits = 8;
				port.Handshake = Handshake.None;
				port.RtsEnable = true;
				port.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);
				port.Open();
				output("serial port " + PORTNAME + "opened");
				return port;
			} catch(Exception exc) {
				reportError("Error opening serial port (" + exc.Message + ")");
				return null;
			}
		}


		private static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e) {
			// we will process one or more messages in a loop
			// WARNING: if for some reason the serial data gets out of sync (first byte isn't 0xE0)
			//			then we will not recover, and the data will not be understood at all!

			byte[] message = new byte[MSGLEN];
			while (true) {
				int count = sp.BytesToRead;
				if (count == 0) return; // no more data, exit the handler
				if (count >= MSGLEN) {
					// we now read exactly 21 bytes, no more no less, so when several messages could be present
					// we only obtain the first one in this iteration of the while loop
					int got=sp.Read(message, 0, MSGLEN);
					if (got == MSGLEN) {
						processMessage(message);
					} else {
						// this should never happen
						reportError("Insufficient data bytes in DataReceivedHandler");
					}
				} else {
					// some bytes are present, but not enough; so wait some more
					Thread.Sleep(100);
				}
			}
		}

		private static void processMessage(byte[] bb) {
			// WARNING: this method gets called by DataReceived handler, so it will NOT run on the GUI thread,
			//			and would need Invoking when used in a Windows Forms project
			int count = bb.Length;
			string s = "Got message: (len="+count.ToString()+"): ";
			foreach (byte b in bb) {
				s += b.ToString("X2") + " ";
			}
			string comment = " ?";
			if (count != MSGLEN) comment = " *** ERROR *** Bad length";
			else if (bb[0] != 0xE0) comment = " *** ERROR *** Bad first byte";
			// some examples of message interpretation
			else if (bb[8] == 0xA5 && bb[9] == 0x00) comment = " = Pause on";
			else if (bb[8] == 0xA6 && bb[9] == 0x00) comment = " = Pause off";
			output(s + comment);
		}

		private static void reportError(string message) {
			output("Error: "+message);
		}

		private static void output(string text) {
			Console.WriteLine(text);
		}
	}
}

I expect the above DataReceivedHandler method is OK, you would have to extend or replace the processMessage() method.

Smile | :)

Luc Pattyn [My Articles]
The Windows 11 taskbar is a disgrace; a third-party add-on is needed to reverse the deterioration. I decline such a downgrade.

Hi

I'm did a little test with you code and seems that is working fine, get the data and write the data like as we want.

During these days I'm goint to trying the code and I let you know.

Thanks a lot of you help.
Regards!!

you're welcome.

Smile | :)

Luc Pattyn [My Articles]
The Windows 11 taskbar is a disgrace; a third-party add-on is needed to reverse the deterioration. I decline such a downgrade.

Has anyone been successful at attaching the Visual Studio remote debugger to any process in the Windows Sandbox VM?

I set my Debug Launch profile to start the application on a remote machine, and it successfully connects to the remote debugger process in the Sandbox, but when it tries to launch the application as configured in the launch profile, it says "Unable to start process <PATH to exe>".

The problem is that the path that it says it's trying to start is the path on my local machine, and not the path I have configured inside the launch profile to start on the remote machine.

Has anyone figured this out?

EDIT: I just realized that this problem is not only with the Sandbox VM, but with any VM on my machine. Frown | :(

The difficult we do right away...
...the impossible takes slightly longer.

modified 5-Apr-24 18:05pm.

I am attempting to write a short program in C# that deals with resistances (in electronics). I would like to be able to parse string values into floating point values. The string can be in the format like 100, 4.7K, 2.2M, or shorthand equivalents like 100, 4K7, 2M2. They should never have more than 3 digits, at least one of which is a whole number part (no more than 2 decimals). Also I would like to be able to display them in similar formats. I've looked into MS documentation, and I'm more confused than ever. When do I need to use (if at all) IFormatProvider, ICustomFormatter, IFormattable, IParsable, etc. I've gone 'round and 'round, and I'm thoroughly at sea. I'm not a new programmer, just a retired one. I wrote code for about 30 years in everything from COBOL to VB.NET (including some C and C++). I don't need someone to write the code for me, but any hints would be much appreciated.

Hah been there done that one - try parsing Murex input. We had to build up a set of patterns to test the input against, it took ages to nail the bulk of the patterns that traders would enter as values and they were not limited to 3 characters.

Test each entry against your pattern list, use any found pattern to parse the values, throw an error if no match is found (and add it to your pattern list).

Oh and forget the existing tools as this falls way outside their design specs.

Never underestimate the power of human stupidity -
RAH
I'm old. I know stuff - JSOP

You mean don't use any of those interfaces, just parse them myself? I'm already kinda of doing that, but I was hoping going the interface method might be more flexible.

I would also write my own Parser because the rules for this are clear. I'm not sure if I would try against a list because there are not much points to test against :
- 1st I would search for the multiplier (if there is one) - m for 0.001, k for 1000 and M for 1000000
- then I would test the value before the multiplier (if there is one)
- last I would look, if you have a multiplier if there is a value after it
-> now build you output-value

That's pretty much the way I am doing it now.

Tracy Dryden wrote:
Also I would like to be able to display them in similar formats.

Two ways to do that after you have parsed.

First keep the original value as a string. You can create a class that has both the parsed value and the original value.

Second create your own format method(s) that take the value and normalize the display. Problem with this is you will need to deal with precision.

Me, wanting to "peek" the "last" entry in a ConcurrentQueue, because the "next" entry I will enqueue needs "prior info" if it exists.

I can use ToArray, and GetEnumerator. Surprising .Last() compiles but I thought I'd "Bing" anyway.

Me: peek last entry in concurrentqueue
Copilot with GPT-4:

Quote:
Certainly! In C#, if you want to peek at the last entry in a ConcurrentQueue, you can use the TryPeek method. Here’s an example:

(Some "wrong" / right code).

Quote:
In this example, the TryPeek method allows you to examine the last item in the queue without removing it. If the queue is empty, it returns false, and you can handle that case accordingly.
If you have any more questions or need further assistance, feel free to ask! 😊

MSDN re: TryPeek:

Quote:
Tries to return an object from the beginning of the ConcurrentQueue<t> without removing it.

Seems it can't differentiate a queue from a stack. Nice. VS is also getting more "aggressive" when it's getting it wrong.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

It is not intelligent.

Marketing sells it like it is, but we are far away from thinking machines. Thumbs Up | :thumbsup:

Bastard Programmer from Hell Suspicious | :suss:

"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

The good thing about the new "AI" tools is that they always give a reasonable and convincing looking answer.... especially when they are wrong.

Besides AI getting it wrong:
1) If you have concurrent writers to the queue you do not know something else does not insert a new "last" item after you checked what it is. This can of course be solved with some locking, but then we are at the next point:
2) If you do not have concurrent writers you can just capture the last item to a variable as you enqueue it.

I'm having a problem with a MessageBox.Show() call.

It's being called from a window that was shown with Form.ShowDialog().

The problem is that the message box sometimes appears behind the dialog box, and makes the dialog box unresponsive until the message box window is found and OK is clicked on it.

This would be terribly confusing for users.

Is there any way to guarantee that a message box is displayed above the form that is calling it?

The difficult we do right away...
...the impossible takes slightly longer.

The problem is that ShowDialog is a blocking call: it doesn't return control to the UI thread until the dialog has been dismissed. And MessageBox.Show is also a blocking call: it's the equivelant of calling ShowDialog on a "normal" form.

You don't really have many options here other than to create your own message box and call Show on that if you must be able to continue working with it visible.

"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!

You need a different "pattern". If the "error" is critical, exit the dialog, then give the message; then "retry" based on ok / cancel. Or the "dialog" might function better as a "wizard" (next; back; cancel).

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I