I'm programming on Visual Studio 2017 and i'm fed up with an error which took my entire day.
More precisely, i'm working on an Serial Communication project.
The code will send on every port availiable (GetPortName()) a string.
I installed a log header (plog) which will log all actions.
For each port, the program will log ("Testing port" port).
The variable which stands for port is "s".
The problem is when i lauch : LOGI << s; everything mess up and got a big error.
I tried "&s" instead of simply "s" on LOGI and i have not got any error but there's an adress like 0059EBF0 instead of the port.
I search and research but found nothing.
Can someone help me please ?
Thanks
for each (String^ s in SerialPort::GetPortNames())
{
SerialPort^ mySerialPort = gcnew SerialPort();
LOGI << &s;
mySerialPort->PortName = s;
mySerialPort->BaudRate = 115200;
mySerialPort->Open();
mySerialPort->Write("q");
String^ incom = mySerialPort->ReadLine();
if (incom == "Okay") {
LOGI << "Tt va bien mon fwewe";
setup = false;
}
mySerialPort->Close();
_getch();
}
Related
I've got C++ code using the Paho MQTTPacket Embedded C++ library to connect to an MQTT broker. When that broker is io.adafruit.com, it works perfectly fine. But when it's my own Mosquitto instance running on my Raspberry Pi, the connection fails. I've narrowed it down to this line in MQTTClient.h, in the MQTT::Client::connect method:
// this will be a blocking call, wait for the connack
if (waitfor(CONNACK, connect_timer) == CONNACK)
The app hangs here for about 30 seconds, and then gets a result other than CONNACK (specifically 0 rather than 2).
I have tried both protocol version 3 (i.e. 3.1) and 4 (i.e. 3.1.1); same result.
My Mosquitto instance has no authentication or passwords set up. I've tried turning on debug messages in the Mosquitto log, but they're not showing anything useful. I'm at a loss. Why might I be unable to connect to Mosquitto from my C++ Paho code?
EDIT: Here's the client code... again, this works fine with Adafruit, but when I point it to my Mosquitto at localhost, it hangs as described. (I've elided the username and password -- I am sending them, but I really don't think those are the issue, since with mosquitto_pub or mosquitto_sub on the command line, I can connect regardless of this, since mosquitto is configured to allow anonymous connections.)
const char* host = "127.0.0.1";
int port = 1883;
const char* clientId = "ZoomBridge";
const char* username = "...";
const char* password = "...";
MQTT::QoS subsqos = MQTT::QOS2;
ipstack = new IPStack();
client = new MQTT::Client<IPStack, Countdown, 30000>(*ipstack);
MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
data.willFlag = 1;
data.MQTTVersion = 3;
data.clientID.cstring = (char*)clientId;
data.username.cstring = (char*)username;
data.password.cstring = (char*)password;
data.keepAliveInterval = 20;
data.cleansession = 1;
int rc = ipstack->connect(host, port);
if (rc != MQTT::SUCCESS) {
cout << "Failed [1] (result " << rc << ")" << endl;
return rc;
}
rc = client->connect(data);
if (rc != MQTT::SUCCESS) {
cout << "Failed [2] (result " << rc << ")" << endl;
ipstack->disconnect();
return rc;
}
As hashed out in the comments.
It looks like you are setting the flag to indicate you want to set a Last Will and Testament for the client (data.willFlag = 1;) but then not passing any topic or payload for the LWT.
If you don't need the LWT then set the flag to 0 (or remove the line settings flag) as it should default to disabled.
Also worth pointing out to clarity, this is all with the Paho Embedded C++ MQTTPacket client not the full blown Paho C++ client.
There are several ways to list serial ports under Windows but I'm not sure what is the proper way: the way that does detect all serial ports that are available.
One good code example is http://www.naughter.com/enumser.html - where there are 9 (nine!) ways of enumerating serial devices.
The question is: what is the optimal way of doing it.
Requirements:
to not open ports in order to check if they are available.
to be able to detect ports with different names than COMx.
to work on Windows XP SP2 or above
void SelectComPort() //added function to find the present serial
{
TCHAR lpTargetPath[5000]; // buffer to store the path of the COMPORTS
DWORD test;
bool gotPort=0; // in case the port is not found
for(int i=0; i<255; i++) // checking ports from COM0 to COM255
{
CString str;
str.Format(_T("%d"),i);
CString ComName=CString("COM") + CString(str); // converting to COM0, COM1, COM2
test = QueryDosDevice(ComName, (LPSTR)lpTargetPath, 5000);
// Test the return value and error if any
if(test!=0) //QueryDosDevice returns zero if it didn't find an object
{
m_MyPort.AddString((CString)ComName); // add to the ComboBox
gotPort=1; // found port
}
if(::GetLastError()==ERROR_INSUFFICIENT_BUFFER)
{
lpTargetPath[10000]; // in case the buffer got filled, increase size of the buffer.
continue;
}
}
if(!gotPort) // if not port
m_MyPort.AddString((CString)"No Active Ports Found"); // to display error message incase no ports found
}
If you can access the registry, the HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\SERIALCOMM key contains a list of COM ports Windows currently supports (in some cases, this information may be stale/incorrect; like, I suspect, when a plug & play device providing serial ports has not completed detection/installation or has been recently removed).
This is the way .NET Framework's SerialPort.GetPortNames() method reports available COM ports, and the above information is derived from the linked page.
Serial ports are very simple devices, dating from the stone age of computing hardware. They don't support Plug & Play, there is no way to tell that somebody plugged in a device. The only thing you can do is discover what ports are available, the SerialPort.GetPortNames() returns the list. Some USB emulators can generate a descriptive name to go with the port name, you can discover those with WMI, Win32_SerialPort class.
None of which helps you discover what COM port is connected to a particular device. Only a human knows, she physically plugged the cable in the connector. You'll need to provide a config UI that lets the user select the port number. A combo box gets the job done. Save the selection in your config data, it is very likely that the device is still connected to the same port the next time your program starts.
This is a modernized version of #michael-jacob-mathew's answer:
#include <iostream>
#include <string>
#include <Windows.h>
bool SelectComPort() //added function to find the present serial
{
char lpTargetPath[5000]; // buffer to store the path of the COMPORTS
bool gotPort = false; // in case the port is not found
for (int i = 0; i < 255; i++) // checking ports from COM0 to COM255
{
std::string str = "COM" + std::to_string(i); // converting to COM0, COM1, COM2
DWORD test = QueryDosDevice(str.c_str(), lpTargetPath, 5000);
// Test the return value and error if any
if (test != 0) //QueryDosDevice returns zero if it didn't find an object
{
std::cout << str << ": " << lpTargetPath << std::endl;
gotPort = true;
}
if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
}
}
return gotPort;
}
It produces the following output on my computer:
COM1: \Device\Serial0
COM3: \Device\VCP0
Modified #Dženan answer to use wide characters and returning list of ints
#include <string>
#include <list>
list<int> getAvailablePorts()
{
wchar_t lpTargetPath[5000]; // buffer to store the path of the COM PORTS
list<int> portList;
for (int i = 0; i < 255; i++) // checking ports from COM0 to COM255
{
wstring str = L"COM" + to_wstring(i); // converting to COM0, COM1, COM2
DWORD res = QueryDosDevice(str.c_str(), lpTargetPath, 5000);
// Test the return value and error if any
if (res != 0) //QueryDosDevice returns zero if it didn't find an object
{
portList.push_back(i);
//std::cout << str << ": " << lpTargetPath << std::endl;
}
if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
}
}
return portList;
}
You can check the windows registry base to list all COM ports. Here is my code > github file
CUIntArray ports;
EnumerateSerialPorts(ports);
for (int i = 0; i<ports.GetSize(); i++)
{
CString str;
str.Format(_T("COM%d"), ports.ElementAt(i));
m_ctlPort.AddString(str);
}
I'm trying to communicate with an USB-uart module using Libserial.
Following is my code for initial part:
serial_port.Open("/dev/ttyUSB0");
if ( ! serial_port.good() )
{
std::cerr << "[" << __FILE__ << ":" << __LINE__ << "] "
<< "Error: Could not open serial port."
<< std::endl ;
exit(1) ;
}
serial_port.SetBaudRate( SerialStreamBuf::BAUD_115200 ) ;
if ( ! serial_port.good() )
{
std::cerr << "Error: Could not set the baud rate." <<
std::endl ;
exit(1) ;
}
When I run it on Ubuntu 12.04 and 13.04 with the same USB module, they all say
Error: Could not set the baud rate.
I did some tests and finally found this error would occur if I set the baud rate as or higher than 115200. It works well on 57600 and 19200.
But I'm wondering is there any possible way for me to set the baud rate as 115200?
I downloaded a serial test tool, it can work as the 115200(but I didn't checked the msg content, I just notice the transmit led is flash).
Or is it the hardware limit so I need to buy another module if I want a higher baud rate?
Thanks
===========
UPDATE:
There is no problem with the hardware. I tested it in Windows VS using 115200 and it works well. But it failed on two Ubuntu desktop(12.04 and 13.04).
I print the baudrate out after I set it
serial_port.SetBaudRate( SerialStreamBuf::BAUD_115200) ;
int rate = serial_port.BaudRate();
cout << SerialStreamBuf::BAUD_115200 << endl;
cout << rate << endl;
the result shows their values are the same, both are 4098.
Then I tried to comment all the .good() part with and after the SetBaudRate part, the program start successfully but the transmit LED doesn't flash. So I think there is really something wrong with the baudrate set so the serial initial failed, although the baudrate it returns is correct.
Now I have no idea what to do next...
in case you need to see all my
code
I'm guessing it's this bug, but haven't verified it.
http://ehc.ac/p/libserial/bugs/10/
Now in SerialStreamBuf.h
enum BaudRateEnum {
BAUD_50 = SerialPort::BAUD_50,
BAUD_75 = SerialPort::BAUD_75,
BAUD_110 = SerialPort::BAUD_110,
BAUD_134 = SerialPort::BAUD_134,
BAUD_150 = SerialPort::BAUD_150,
BAUD_200 = SerialPort::BAUD_200,
BAUD_300 = SerialPort::BAUD_300,
BAUD_600 = SerialPort::BAUD_600,
BAUD_1200 = SerialPort::BAUD_1200,
BAUD_1800 = SerialPort::BAUD_1800,
BAUD_2400 = SerialPort::BAUD_2400,
BAUD_4800 = SerialPort::BAUD_4800,
BAUD_9600 = SerialPort::BAUD_9600,
BAUD_19200 = SerialPort::BAUD_19200,
BAUD_38400 = SerialPort::BAUD_38400,
BAUD_57600 = SerialPort::BAUD_57600,
BAUD_115200 = SerialPort::BAUD_115200, // 4098
BAUD_230400 = SerialPort::BAUD_230400,
#ifdef __linux__
BAUD_460800 = SerialPort::BAUD_460800,
#endif
BAUD_DEFAULT = SerialPort::BAUD_DEFAULT, // 4097
BAUD_INVALID
} ;
So BAUD_INVALID will be 4098, exactly the same as BAUD_115200. That's why you get error.
hello i had the same problem and even i tried everything using c++ API for libSerial couldn't solve until i used the bellow code in my serial initialization!!
I used the system call once at the initialization and that worked GREAT!!
NOTE instead of /dev/ttyACM0 use the name of your serial device /dev/ttyXXX
LibSerial::SerialStream serial;
//serial.SetBaudRate(LibSerial::SerialStreamBuf::BAUD_9600);//THAT DOESNT WORKS
serial.SetCharSize( LibSerial::SerialStreamBuf::CHAR_SIZE_8);
serial.Open("/dev/ttyACM0");
system("sudo stty -F /dev/ttyACM0 115200");//YOU HAVE TO RUN THE EXCECUTABLE FROM COMMAND LINE WITH SU PRIVILEGES
We are using FTDI serial port CHIP in our hardware. Now we have working code in Linux and we moved to windows 7. We get some weird problems.
The Problem:
We can't write data to Serial Port without running other console application which do this:
serial.setPortName("COM3");
if (serial.open(QIODevice::ReadWrite)) {
bool success = serial.setBaudRate(QSerialPort::Baud9600) &
serial.setStopBits(QSerialPort::OneStop) &
serial.setDataBits(QSerialPort::Data8) &
serial.setParity(QSerialPort::NoParity) &
serial.setFlowControl(QSerialPort::NoFlowControl);
qDebug() << "Connected to usb device: " << (success ? "OK" : "FAIL");
while(true) {
if(serial.waitForReadyRead(-1)) {
QByteArray out = serial.readAll();
for(int i=0; i< out.length(); i++) {
qDebug() << (int) out[i];
}
}
}
serial.close();
So its just loop with read all. Hardware dosen't send anything, so read is just infinity loop. After closing and running our write program it runs correctly.
char* input;
input = new char[size+3];
QByteArray bytearr;
for(int i=0;i<size+2;i++) {
input[i] = (char) package[i];
bytearr.append((unsigned char) package[i]);
}
QString serialPortName = "COM3";
QSerialPort serialPort;
serialPort.setPortName(serialPortName);
serialPort.open(QIODevice::ReadWrite);
serialPort.write(bytearr);
serialPort.flush();
serialPort.close();
After running read everything works, but without read all, it wont work. What are we doing wrong?
Thanks.
We had similar problem in our application with a board with FTDI chip. We tried to write bytes with 19200 baud/sec, had though in real about 1200 baud/sec (seen using oscilloscope). The problem was closing the serial port right after writing a byte. Just waiting using QThread::msleep(5) before closing the port helped. It seems, that the device gets a reset or something during close operation and latest bytes are sent with false baudrate and other parameters.
I found out that the QT serial port SW requires you to process QT events in order to work.
Putting a qApp->processEvents() in the loop before the read made it work for me.
(QT 4.8.5 on Windows-7)
Problem:
I have a hand held device that scans those graphic color barcodes on all packaging. There is a track device that I can use that will slide the device automatically. This track device functions by taking ascii code through a serial port. I need to get this thing to work in FileMaker on a Mac. So no terminal programs, etc...
What I've got so far:
I bought a Keyspan USB/Serial adapter. Using a program called ZTerm I was successful in sending commands to the device.
Example:
"C,7^M^J"
I was also able to do the same thing in Terminal using this command: screen /dev/tty.KeySerial1 57600
and then type in the same command above(but when I typed in I just hit Control-M and Control-J for the carriage return and line feed)
Now I'm writing a plug-in for FileMaker(in C++ of course). I want to get what I did above happen in C++ so when I install that plug-in in FileMaker I can just call one of those functions and have the whole process take place right there.
I'm able to connect to the device, but I can't talk to it. It is not responding to anything.
I've tried connecting to the device(successfully) using these:
FILE *comport;
if ((comport = fopen("/dev/tty.KeySerial1", "w")) == NULL){...}
and
int fd;
fd = open("/dev/tty.KeySerial1", O_RDWR | O_NOCTTY | O_NDELAY);
This is what I've tried so far in way of talking to the device:
fputs ("C,7^M^J",comport);
or
fprintf(comport,"C,7^M^J");
or
char buffer[] = { 'C' , ',' , '7' , '^' , 'M' , '^' , 'J' };
fwrite (buffer , 1 , sizeof(buffer) , comport );
or
fwrite('C,7^M^J', 1, 1, comport);
Questions:
When I connected to the device from Terminal and using ZTerm, I was able to set my baud rate of 57600. I think that may be why it isn't responding here. But I don't know how to do it here.... Does any one know how to do that? I tried this, but it didn't work:
comport->BaudRate = 57600;
There are a lot of class solutions out there but they all call these include files like termios.h and stdio.h. I don't have these and, for whatever reason, I can't find them to download. I've downloaded a few examples but there are like 20 files in them and they're all calling other files I can't find(like the ones listed above). Do I need to find these and if so where? I just don't know enough about C++ Is there a website where I can download libraries??
Another solution might be to put those terminal commands in C++. Is there a way to do that?
So this has been driving me crazy. I'm not a C++ guy, I only know basic programming concepts. Is anyone out there a C++ expert? I ideally I'd like this to just work using functions I already have, like those fwrite, fputs stuff.
Thanks!
Sending a ^ and then a M doesn't send control-M, thats just the way you write it,
to send a control character the easiest way is to just use the ascii control code.
ps. ^M is carriage return ie "\r" and ^J is linefeed "\n"
edit: Probably more than you will (hopefully) ever need to know - but read The Serial Port Howto before going any further.
This isn't a C++ question. You're asking how to interact with the TTY driver to set teh baud rate. The fact that you're opening the file under /dev tells me that you're on a unix derivative, so the relevant man page to read on a linux system is "man 3 termios".
Basically, you use the open() variant above, and pass the file descriptor to tcsetattr/tcgetattr.
Are you sure you've installed all the compiler tools properly? On my OS X 10.5.8 Mac,
termios.h and stdio.h are right there under /usr/include, just as I'd expect. The
code you've already found for serial port programming on other Unix variants should
only require minor changes (if any) to work on a Mac. Can you tell us a bit more about
what you've tried, and what went wrong?
mgb also has a good point about how the control characters need to be represented.
You can set the baud rate with ioctl. Here's a link to an example.
You don't specify which Unix you are using, so below I'm posting some Linux production code I use.
Pleae note below code is a class method so ignore any external (ie undeclared) references.
Steps are as follows -
Configure your termio structure, this is where you set any needed flags etc (ie the step you accomplished using zterm. The termio settings below configure the port to 8 databits, 1 stopbit and no parity (8-n-1). Also the port will be in "raw" (as opposed to cooked) mode so its a character stream, text isn't framed into lines etc The baud constants match the actual value, ie for 56700 baud you use "57600".
The timing parameters mean that characters are returned from the device as soon as they are available.
Once you have your termainal parameters set, you open the device (using POSIX open()), and then can use tcgetattr/tcsetattr to configure the device via the fd.
At this point you can read/write to the device using the read()/write() system calls.
Note that in the below example read() will block if no data is available so you may want to use select()/poll() if blocking is undesirable.
Hope that helps.
termios termio
tcflag_t baud_specifier;
//reset device state...
memset (&termio, 0, sizeof (termios));
read_buffer.clear();
//get our boad rate...
if (!(baud_specifier = baud_constant (baud))) {
ostringstream txt;
txt << "invalid baud - " << baud;
device_status_msg = txt.str();
status = false;
return (true);
}
//configure device state...
termio.c_cflag = baud_specifier | CS8 | CLOCAL | CREAD;
//do we want handshaking?
if (rtscts) {
termio.c_cflag |= CRTSCTS;
}
termio.c_iflag = IGNPAR;
termio.c_oflag = 0;
termio.c_lflag = 0;
//com port timing, no wait between characters and read unblocks as soon as there is a character
termio.c_cc[VTIME] = 0;
termio.c_cc[VMIN] = 0;
//open device...
if ((fd = open (device.c_str(), O_RDWR | O_NOCTTY)) == -1) {
ostringstream txt;
txt << "open(\"" << device << "\") failed with " << errno << " - "
<< std_error_msg (errno);
device_status_msg = txt.str();
status = false;
return (true);
}
//keep a copy of curret device state...
if (tcgetattr (fd, &old_termio) == -1) {
ostringstream txt;
txt << "tcgetattr() failed with " << errno << " - " << std_error_msg (errno);
device_status_msg = txt.str();
status = false;
return (true);
}
//flush any unwanted bytes
if (tcflush (fd, TCIOFLUSH) == -1) {
ostringstream txt;
txt << "tcflush() failed with " << errno << " - " << std_error_msg (errno);
device_status_msg = txt.str();
status = false;
return (true);
}
//apply our device config...
if (tcsetattr (fd, TCSANOW, &termio) == -1) {
ostringstream txt;
txt << "tcsetattr() failed with " << errno << " - " << std_error_msg (errno);
device_status_msg = txt.str();
status = false;
return (true);
}
node_log_f ("successfully initialised device %s at %i baud", "open_device()",
device.c_str(), baud);
status = true;
return (true);
}