Develop Reference

FTDI Multithreaded Read

I have the following problem and hope someone can help me.
My basic flow: I want to program any number of devices in parallel using the FTDI D2XX driver and then communicate with them for testing purposes. For this I use two arrays from BackgroundWorker - the first array for programming and the second for testing.
Programming works without any problems. But if I start the BackgroundWorker from the second array to start the test, the connection fails. If I run the complete sequence with only one BackgroundWorker for programming and one BackgroundWorker for testing, the sequence works without problems.
Initialization of BackgroundWorker
private void InitializeBackgoundWorkers()
{
for (var f = 0; f < ftdiDeviceCount; f++)
{
threadArrayProgram[f] = new BackgroundWorker();
threadArrayProgram[f].DoWork += new DoWorkEventHandler(bgr_WorkerStirrerProg_DoWork);
threadArrayProgram[f].RunWorkerCompleted += new RunWorkerCompletedEventHandler(BackgroundWorkerProgRunWorkerCompleted);
threadArrayProgram[f].WorkerReportsProgress = true;
threadArrayProgram[f].WorkerSupportsCancellation = true;
}
for (var f = 0; f < ftdiDeviceCount; f++)
{
threadArrayTest[f] = new BackgroundWorker();
threadArrayTest[f].DoWork += new DoWorkEventHandler(bgr_WorkerStirrerTest_DoWork);
threadArrayTest[f].RunWorkerCompleted += new RunWorkerCompletedEventHandler(BackgroundWorkerTestRunWorkerCompleted);
threadArrayTest[f].WorkerReportsProgress = true;
threadArrayTest[f].WorkerSupportsCancellation = true;
}
}
Aufruf der BackgroundWorker
private void button2_Click_1(object sender, EventArgs e)
{
if (!bStirrerSerached)
{
vSetProgressBarValueRuehrer(1, imaxprogressbar);
vSearchStirrer();
}
if (FtStatus == FTDI.FT_STATUS.FT_OK)
{
//bgr_Worker_Stirrer.RunWorkerAsync();
InitializeBackgoundWorkers();
//---programmieren---//
for (var f = 0; f < /*FilesToProcess*/ftdiDeviceCount; f++)
{
var fileProcessed = false;
while (!fileProcessed)
{
for (var threadNum = 0; threadNum < MaxThreads; threadNum++)
{
if (!threadArrayProgram[threadNum].IsBusy)
{
Console.WriteLine("Starting Thread: {0}", threadNum);
stemp = "Starting Thread: " + threadNum;
File.AppendAllText(slogfile, stemp);
threadArrayProgram[threadNum].RunWorkerAsync(f);
fileProcessed = true;
Thread.Sleep(1000);
break;
}
}
if (!fileProcessed)
{
Thread.Sleep(50);
}
}
}
//---testen---//
for (var f = 0; f < /*FilesToProcess*/ftdiDeviceCount; f++)
{
var fileProcessed = false;
while (!fileProcessed)
{
for (var threadNum = 0; threadNum < MaxThreads; threadNum++)
{
if (!threadArrayTest[threadNum].IsBusy)
{
Console.WriteLine("Starting Thread: {0}", threadNum);
stemp = "Starting Thread: " + threadNum;
File.AppendAllText(slogfile, stemp);
threadArrayTest[threadNum].RunWorkerAsync(f);
fileProcessed = true;
Thread.Sleep(1000);
break;
}
}
if (!fileProcessed)
{
Thread.Sleep(50);
}
}
}
}
button2.Enabled = false;
}
BackgroundWorker
private void bgr_WorkerStirrerProg_DoWork(object sender, DoWorkEventArgs e)
{
try
{
if (FtStatus == FTDI.FT_STATUS.FT_OK)
{
if (ftdiDeviceList != null)
{
//---db werte sammeln---//
cRuehrerProp = new CRuehrerProperties();
cRuehrerProp.SBenutzer = System.Security.Principal.WindowsIdentity.GetCurrent().Name;
cRuehrerProp.SComputername = System.Windows.Forms.SystemInformation.ComputerName.ToString();
//---Rührer programmieren---//
vStirrerProgram((int)e.Argument);
}
}
}
catch (NotSupportedException /*exc*/)
{
}
finally
{
this.Invoke((MethodInvoker)delegate
{
});
}
}
private void bgr_WorkerStirrerTest_DoWork(object sender, DoWorkEventArgs e)
{
try
{
if (!bfinish)
{
while (!bfinish)
{
if (bfinish)
break;
}
}
//---Test starten---//
vStirrerTest((int)e.Argument);
}
catch (NotSupportedException /*exc*/)
{
}
finally
{
this.Invoke((MethodInvoker)delegate
{
button2.Enabled = true;
myFtdiDevice.Close();
});
}
}
Testing method
private void vStirrerTest(int pos)
{
//threadnr
iPosRuehrerGrid = pos;
Console.WriteLine("Thread {0} StirrerTest", pos);
ftStatus = myFtdiDevice.CyclePort();
UInt32 newFtdiDeviceCount = 0;
do
{
// Wait for device to be re-enumerated
// The device will have the same location since it has not been
// physically unplugged, so we will keep trying to open it until it succeeds
ftStatus = myFtdiDevice.OpenByLocation(ftdiDeviceList[iPosRuehrerGrid].LocId);
Console.WriteLine("try to open locid" + ftdiDeviceList[iPosRuehrerGrid].LocId + " on device " + iPosRuehrerGrid);
//ftStatus = myFtdiDevice.OpenByLocation(ftdiDeviceListOrig[iStirrerPosold[iPosRuehrerGrid]].LocId);
Thread.Sleep(1000);
} while (ftStatus != FTDI.FT_STATUS.FT_OK);
// Close the device
myFtdiDevice.Close();
// Re-create our device list
ftStatus = myFtdiDevice.GetNumberOfDevices(ref newFtdiDeviceCount);
if (ftStatus != FTDI.FT_STATUS.FT_OK)
{
// Wait for a key press
Console.WriteLine("Failed to get number of devices (error " + ftStatus.ToString() + ")");
stemp = "Failed to get number of devices (error " + ftStatus.ToString() + ")";
File.AppendAllText(slogfile, stemp);
return;
}
// Re-populate our device list
ftStatus = myFtdiDevice.GetDeviceList(ftdiDeviceList);
bRepopulateList = true;
vSearchStirrer();
The error occurs in the do loop. If I use only one device - and thus only one thread at a time, it takes an average of 5 runs until the device is opened again. However, if I attach another device and thus have 2 programming and 2 test threads, it does not manage to open the desired device.
I have looked at the DeviceList to make sure it is looking for the right device with the right ID - which it is.
Since I don't have any experience with the Backgrounworker yet, I'm not sure if I haven't forgotten something, which is why this error occurs.

C#: Task Factory starts task repeatedly?

I have a probably simple question about the task factory. I have to following code:
In this task is a loop that is polling data from the RS232 and a counter that stops polling after 10 times. After this "doCollect" will be set to false.
And now comes the strange thing: The task runs repeatedly. The caller code is:
// class Main()
RS232DataAquisition _RS232DataAquisition = new RS232DataAquisition();
public override void Run()
{
System.Diagnostics.Stopwatch timeout = new System.Diagnostics.Stopwatch();
timeout.Start();
_RS232DataAquisition.Start();
while ((timeout.ElapsedMilliseconds <= (dataGatherTime_inSeconds * 1000)) && _RS232DataAquisition.DoCollect)
{
System.Threading.Thread.Sleep(100);
}
timeout.Stop();
_RS232DataAquisition.Stop();
}
Per my understanding the Run() function should start the thread and return into the while-loop waiting for the thread to finish. But it never does?!
Here's the code for ReadDataFromRS232:
// sealed class RS232DataAquisition
private bool doCollect = false;
public bool DoCollect
{
get { return doCollect; }
}
public void Start()
{
doCollect = true;
currentTask = System.Threading.Tasks.Task.Factory.StartNew(() =>
{
this.ReadDataFromRS232();
});
}
private void ReadDataFromRS232(int NumtoRead = 10)
{
var port = new System.IO.Ports.SerialPort(PortName);
int waitCount = 5;
var portExists = System.IO.Ports.SerialPort.GetPortNames().Any(x => x == PortName);
if (!portExists)
{
throw new ArgumentException("Port does not exist!");
}
while (port.IsOpen && waitCount-- > 0)
{
doCollect = false;
Wait();
}
doCollect = true;
if (!port.IsOpen)
{
port.Open();
port.NewLine = _NewLine;
port.ReadTimeout = 2000;
int number;
try { }
finally { }
port.Write("flashon\r");
while (doCollect && (_readCounter <= NumtoRead))
{
string s;
try
{
s = port.ReadLine();
}
catch
{
s = "-1";
}
int i;
if (int.TryParse(s, out i))
{
number = Convert.ToInt32(s, 10);
}
else
{
number = 0;
}
lock (thisLock) _data.Add(number);
_readCounter++;
}
port.Write("flashoff\r");
port.Close();
port.Dispose();
Wait(); Wait();
}
}
private void Wait()
{
System.Threading.Thread.Sleep(10);
System.Threading.Thread.SpinWait(1);
}
I don't get, why "ReadDataFromRS232" is beeing repeated until the timeout stops this task.
Thank you for any help :)
EDIT: Added some missing code.

As Dennis said the problem seemed to come from the missing volatile. It works now even though I have no idea why it didn't before.

Ping Completed Event Handler not working [closed]

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Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 7 years ago.
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When I execute this code in command line, it's working fine:
class Program
{
private static List<Ping> pingers = new List<Ping>();
private static List<string> value = new List<string>();
private static int instances = 0;
private static object #lock = new object();
private static int result = 0;
private static int timeOut = 2500;
private static int ttl = 7;
public static void Main()
{
string baseIP = "192.168.1.";
Console.WriteLine("Pinging destinations of D-class in {0}*", baseIP);
CreatePingers(254);
PingOptions po = new PingOptions(ttl, true);
System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();
byte[] data = enc.GetBytes("");
SpinWait wait = new SpinWait();
int cnt =1;
Stopwatch watch = Stopwatch.StartNew();
foreach (Ping p in pingers)
{
lock (#lock)
{
instances += 1;
}
p.SendAsync(string.Concat(baseIP, cnt.ToString()), timeOut, data, po);
cnt += 1;
}
//while (instances > 0)
//{
// wait.SpinOnce();
//}
watch.Stop();
for (int i = 0; i < value.Count; i++)
{
Console.WriteLine(value[i]);
}
DestroyPingers();
Console.WriteLine("Finished in {0}. Found {1} active IP-addresses.", watch.Elapsed.ToString(), result);
Console.ReadKey();
}
public static void Ping_completed(object s, PingCompletedEventArgs e)
{
lock (#lock)
{
instances -= 1;
}
if (e.Reply.Status == IPStatus.Success)
{
string sa = string.Concat("Active IP: ", e.Reply.Address.ToString());
value.Add(sa);
//Console.WriteLine(sa);
String diachiip = e.Reply.Address.ToString();
result += 1;
}
else
{
//Console.WriteLine(String.Concat("Non-active IP: ", e.Reply.Address.ToString()))
}
}
private static void CreatePingers(int cnt)
{
for (int i = 1; i <= cnt; i++)
{
Ping p = new Ping();
p.PingCompleted += Ping_completed;
pingers.Add(p);
}
}
private static void DestroyPingers()
{
foreach (Ping p in pingers)
{
p.PingCompleted -= Ping_completed;
p.Dispose();
}
pingers.Clear();
}
}
But when I convert from it to window form, it doesn't work. I don't kwow why, I have tried many different ways...
Code is here:
public partial class Form1 : Form
{
public static List<Ping> pingers = new List<Ping>();
public static List<string> value = new List<string>();
public static int instances = 0;
public static object #lock = new object();
public static int result = 0;
public int timeout = 2500;
public static int ttl = 7;
public Form1()
{
InitializeComponent();
}
public void btnscan_Click(object sender, EventArgs e)
{
string baseIP = "192.168.1.";
//int kt = Int32.Parse(txtkt.Text);
//int start = Int32.Parse(txtstart.Text);
CreatePingers(254);
PingOptions po = new PingOptions(ttl, true);
System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();
byte[] data = enc.GetBytes("");
int cnt = 1;
Stopwatch watch = Stopwatch.StartNew();
foreach (Ping p in pingers)
{
lock (#lock)
{
instances += 1;
}
p.SendAsync(string.Concat(baseIP, cnt.ToString()), timeout, data, po);
cnt += 1;
}
watch.Stop();
//Result alway return 0
lst1.Items.Add(result.ToString());
lst1.Items.Add(value.Count.ToString());
for (int i = 0; i < value.Count; i++)
{
lst1.Items.Add(value[i]);
lst1.Items.Add("\n");
}
DestroyPingers();
string a = "Finished in " + watch.Elapsed.ToString() + ". Found " + result + " active IP-addresses.";
lst1.Items.Add(a);
}
public static void CreatePingers(int kt)
{
for (int start = 1; start <= kt; start++)
{
// class System.Net.NetworkInformation.Ping
Ping p = new Ping();
p.PingCompleted += Ping_completed();
pingers.Add(p);
}
}
public static PingCompletedEventHandler Ping_completed()
{
PingCompletedEventHandler a = new PingCompletedEventHandler(abc);
return a;
}
static void abc(object s, PingCompletedEventArgs e)
{
value.Add("abc");
lock (#lock)
{
instances -= 1;
}
if (e.Reply.Status == IPStatus.Success)
{
string abcd = string.Concat("Active IP: ", e.Reply.Address.ToString());
value.Add(abcd);
result += 1;
}
}
public static void DestroyPingers()
{
foreach (Ping p in pingers)
{
p.PingCompleted -= Ping_completed();
p.Dispose();
}
pingers.Clear();
}
}
What is wrong in this code?

Method SendAsync returns 0 because you are not waiting for it to complete. You are missing await and async (see msdn):
async void btnscan_Click(object sender, EventArgs e)
{
...
await p.SendAsync(string.Concat(baseIP, cnt.ToString()), timeout, data,
...
}
SpinWait was making code to work in console application. In winforms you should not use SpinWait (nor Sleep) in UI thread. You can create another thread (e.g. by using Task) and then you can copy/paste code from console application 1-to-1. But then you will need to use Invoke each time when you want to access UI controls.
async/await is really better.. if it will work (I concluded that from method name, I've no idea what method does, nor how to use it).
Perhaps I miss one thing, if SendAsync returns value, then you can get it by (the requirement to mark method where you use await with async still):
var result = await p.SendAsync(...);

Multithread with TCPclient

I do have a problem with a multithreaded TCPClient application, every Client object has a Thread that recievies and sends messages and a thread that handle the Tasks that should be handled (depending on the messages)... (for example creates and answer that the msg threads sends). But something is going wrong... the application almost allways uses 100% cpu (if any thread have a task, and thats most of the time). I also have a feeling that some threads get prioritised less then others (can see in some loggs that an operation takes longer in thread 1 then in thread 2 for exampel... Is there any nice way to handel this problem?
I would love some help or some hints!
Anything unclear just ask :)
Thanks! /Nick
//Waiting for TCP-connections and creating them as they arrive. Starts a Thread that handles the messages recieved and sent with this thread.
private void ListenForClients()
{
try
{
this.tcpListener.Start();
while (true)
{
TcpClient client = this.tcpListener.AcceptTcpClient();
Connection c = new Connection(this.parent);
connectionCollection.Add(c);
Thread clientThread = new Thread(new ParameterizedThreadStart(c.HandleClientComm));
threadCollection.Add(clientThread);
clientThread.Start(client);
}
}
catch (Exception e)
{
}
}
//Connection constructor, creates a ToDo-thread, this handles the messages (DB, Filewriting etc.) recieived and creats new ones to be sent.
public Connection()
{
this.todo = new ArrayList();
todoT = new Thread(handleToDo);
todoT.Start();
}
//Messagehandeling-thread
public void HandleClientComm(object client)
{
try
{
TcpClient server = (TcpClient)client;
NetworkStream ns = server.GetStream();
byte[] data = new byte[1024];
string input, stringData;
online = true;
DateTime lastTime = DateTime.Now;
while (true && this.online)
{
try
{
if (lastTime.AddMinutes(2) < DateTime.Now)
break;
data = new byte[1024];
if (ns.DataAvailable && ns.CanRead)
{
int recv = ns.Read(data, 0, data.Length);
if (recv > 0)
{
lastTime = DateTime.Now;
if ((byte)data[recv - 1] == (byte)255)
{
int cnt = -1;
for (int i = 0; i < recv; i++)
{
if (data[i] == (byte)254)
{
cnt = i;
break;
}
}
int nr = recv - cnt - 2;
byte[] tmp = new byte[nr];
for (int i = 0; i < nr; i++)
{
tmp[i] = data[cnt + i + 1];
}
string crc = Encoding.UTF8.GetString(tmp);
stringData = Encoding.UTF8.GetString(data, 0, cnt);
MsgStruct msgs = new MsgStruct(stringData);
msgs.setCrc(crc);
addTodo(msgs);
if (msgs.getMsg()[0] == 'T' && this.type == 1)
this.parent.cStructHandler.sendAck(msgs, this.ID);
Console.WriteLine(todo.Count);
}
}
}
if (parent.cStructHandler.gotMsg(this.ID))
{
MsgStruct tmpCs = parent.cStructHandler.getNextMsg(this.ID);
if (tmpCs.getMsg().Length != 0 && ns.CanWrite)
{
byte[] ba = Encoding.UTF8.GetBytes(tmpCs.getMsg());
if (tmpCs.getCrc() == "")
{
ulong tmp = CRC.calc_crc(ba, ba.Length);
tmpCs.setCrc(tmp.ToString("X"));
}
if (tmpCs.canSendByTimeout())
{
string crcStr = "?" + tmpCs.getCrc() + "?";
byte[] bb = Encoding.UTF8.GetBytes(crcStr);
crcStr = Encoding.UTF8.GetString(bb);
byte[] fullMsg = new byte[ba.Length + bb.Length];
bb[0] = 254;
bb[bb.Length - 1] = 255;
ba.CopyTo(fullMsg, 0);
bb.CopyTo(fullMsg, ba.Length);
string s = System.Text.UTF8Encoding.ASCII.GetString(fullMsg);
ns.Write(fullMsg, 0, fullMsg.Length);
if (!tmpCs.isAckNeeded())
parent.cStructHandler.removeNextMsg(this.ID);
}
}
}
}
catch (Exception e)
{
break;
}
}
ns.Close();
server.Close();
dead = true;
}
catch (Exception e)
{
dead = true;
}
}
//Todo-thread
public void handleToDo()
{
try
{
int cnt = 0;
while (true)
{
if (todo.Count > 0)
{
//SWITCH CASE FOR DIFFERENT MESSAGE TYPES, DOING TASKS DEPENDING ON WHAT ONES...
}
else
{
if (dead)
{
todoT.Abort();
todoT = null;
break;
}
}
}
}
}

Stop checking if data is available etc. and just let the read() block. That's how it's supposed to work!
If you want to write stuff to the socket, do it from another thread, (direct from parent thingy?), or change your design to use async reads/writes.
Looping around, polling stuff, sleep() etc. is just a waste of CPU and/or adding avoidable latency to your app.

how do i reset the timer at the end of the day automatically?

How do i reset the timer at the end of the day automatically and how do i display the time and date it was executed the last time?
The program is -
namespace Time_Writer
{
class Program
{
static int count = 1;
static double seconds;
static int total = 10000;
private static System.Timers.Timer aTimer;
static void Main(string[] args)
{
ReadCountFromFile();
aTimer = new System.Timers.Timer();
aTimer.Elapsed +=new System.Timers.ElapsedEventHandler(aTimer_Elapsed);
aTimer.Interval = 5000;
aTimer.Enabled = true;
Console.WriteLine("Press Enter To Exit The Program\n");
Console.ReadLine();
AppDomain.CurrentDomain.ProcessExit += new EventHandler(CurrentDomain_ProcessExit);
}
private static void ReadCountFromFile()
{
try
{
if (File.Exists(".\\mynumber.dat"))
{
using (var file = File.Open(".\\mynumber.dat", FileMode.Open))
{
byte[] bytes = new byte[4];
file.Read(bytes, 0, 4);
count = BitConverter.ToInt32(bytes, 0);
total = total - count;
Console.WriteLine("Total count left is = {0}", total);
Console.WriteLine("Limit = 10000");
Console.WriteLine("Count = {0}", count);
}
}
}
catch (Exception ex)
{
Console.WriteLine("Problem reading file.");
}
}
static void CurrentDomain_ProcessExit(Object sender, EventArgs e)
{
using (var file = File.Open(".\\mynumber.dat", FileMode.OpenOrCreate))
{
var buffer = BitConverter.GetBytes(count);
file.Write(buffer, 0, buffer.Length);
}
}
private static void aTimer_Elapsed(object source, ElapsedEventArgs e)
{
Console.WriteLine("Name is Yap {0}", e.SignalTime);
seconds += 5;
count += 1;
if (count>10000 || seconds == 86400)
{
aTimer.Enabled = false;
Console.WriteLine("\n\nTimer is off at {0}\n\n", e.SignalTime.TimeOfDay.ToString());
}
}
}
}

I modify your code and wrap your timer into a thread. I reduces the timer and count as well to make it easier to test. I'm sure there is a much better way to code it but this solution seems to work. you may need to adjust the thread sleep according to your need.
You can adjust when the process should stop and restart by playing with the condition
if (count > TOTAL || _processStart.AddSeconds(1) < DateTime.Now) )
in the function aTimer_Elapsed.
Currenlty the process restart if it has been running for more than 1s or the count is reach.
class Program
{
private static DateTime _processStart;
static int count = 1;
const int TOTAL = 15;
private static Timer aTimer;
private static Thread _process;
static void Main(string[] args)
{
_process = new Thread(DoProcess);
_process.Start();
Console.WriteLine("Press Enter To Exit The Program\n");
Console.ReadLine();
ProcessExit();
}
static void DoProcess()
{
_processStart = DateTime.Now;
ReadCountFromFile();
if (count < TOTAL)
{
Console.WriteLine("******START TIMER******");
aTimer = new Timer();
aTimer.Elapsed += aTimer_Elapsed;
aTimer.Interval = 500;
aTimer.Enabled = true;
while (aTimer.Enabled)
{
Thread.Sleep(1000);
}
Console.WriteLine("******END TIMER******");
ProcessExit();
DoProcess();
}
}
private static void ReadCountFromFile()
{
try
{
if (File.Exists(".\\mynumber.dat"))
{
using (var file = File.Open(".\\mynumber.dat", FileMode.Open))
{
byte[] bytes = new byte[4];
file.Read(bytes, 0, 4);
count = BitConverter.ToInt32(bytes, 0);
Console.WriteLine("Total count left is = {0} / Limit = {1} / Count = {2}", TOTAL - count, TOTAL, count);
}
}
}
catch (Exception ex)
{
Console.WriteLine("Problem reading file.");
}
}
static void ProcessExit()
{
using (var file = File.Open(".\\mynumber.dat", FileMode.OpenOrCreate))
{
var buffer = BitConverter.GetBytes(count);
file.Write(buffer, 0, buffer.Length);
}
}
private static void aTimer_Elapsed(object source, ElapsedEventArgs e)
{
//Console.WriteLine("Name is Yap {0}", e.SignalTime);
if (count < TOTAL)
{
count += 1;
Console.WriteLine("Count is {0}", count);
}
if (count > TOTAL || _processStart.AddSeconds(1) < DateTime.Now)
{
aTimer.Enabled = false;
Console.WriteLine("Timer is off at {0} count is {1}", e.SignalTime.TimeOfDay.ToString(),count);
}
}
}