I'm trying to use a C++ program to communicate through a serial port on Ubuntu 10.04. I've installed LibSerial and for now I'm using virtual serial ports using socat. I'm getting an error on compiling (found below). But step by step, first I start the virtual serial ports:
Code:
(MYNAME@MYCOMPUTER):~$ socat -d -d PTY: PTY:
2010/10/17 22:04:18 socat[18575] N PTY is /dev/pts/2
[code]....
I'm currently working on a project for university that requires communication, via an RS232 link between a piece of hardware (I have designed and am currently testing) and some software(which need testing).
I was hoping to have my hardware finished by now so I could get on with testing the software over Easter.
The hardware does not work yet but I would still like to test the software.
Does any one know if there a way to make a virtual serial port that I could put data on and read data off while my program accesses it as a regular serial port so I can check my code?
I am using Ubuntu 9.10 and am happy to give any more information on request.
I want to create a virtual serial port in Fedora. I'm using Java code to communicate over a serial port. I want to test this code with out any serial devices connected.
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1) Standard serial communications
2) TCPIP over serial via PPP
3) TCPIP over Ethernet
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I have a serial port program which is reading a string .if(read(readfd,sResult,1)>0)where sResult is unsigned char sResult[10];if sResult is array of 10 then iam getting string perfectly but if iam making sResult only as unsigned char I am getting NULL value CODE BELOW
Code:
unsigned char sResult;
main()
{
readfd = open("/dev/ttyUSB0", O_RDONLY);
if (readfd == -1)
{
perror("READ: open_port: Unable to open /dev/ttyUSB0-
[Code]...
Basically I'm intending to write serial RX signal handler.Application receives defined packages of data over serial which contains header and payload. Handler should analyse incoming stream and upon detection of header (header is 6B in length) switches to receive payload of length defined in header, then after receiving full message packs it and sends to application for handling.Problem I'm facing is that at random moments in signal I receive errors that "Resource temporarily unavailable" while reading from ttyOx device and I see that sometimes I miss incoming data.Also is it possible that if while I'm handling signal one more signal arrives and it is started to be handled parallel? If it is, what are the ways to prevent it? So I would be sure that no more signals will fire on same peripheral until I will finish handling what I have on my hands now.
Serial open and init:
Code: Select allint open_port(int port_nr) {
int fd; /* File descriptor for the port */
switch (port_nr) {
case 1:
fd = open("/dev/ttyO1", O_RDWR | O_NOCTTY | O_NDELAY);
break;
[code]....
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# int main()
{
if (openport()<0)
[code]...
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Code:
COMMTIMEOUTS CommTimeouts;
[...]
CommTimeouts.ReadIntervalTimeout = 2;
[code]....
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Code:
AT$GPSACP
$GPSACP: 104323.000,4x45.6171N,00x38.6219E,0.8,446.5,3,272.14,0.21,0.11,080311,09
[code]...
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Code:
int x=0;
int actual_module()
{ int k;
mm_segment_t oldfs;
[code]....
how to configure serial port RS-232 to use flow control? The reason is without flow control is is not working properly(dala loss etc.) Im trying to run it as it is just with setting the flow control flag and Im sending my data via loop-back on the rs-232 to GTK TERM on the same computer... but when I enable IXON/IXOFF in GTK TERM, my sending program cant even open the port...
My current settings is:
Code:
struct termios termios_p;
//ferme_port();
tcgetattr(sc.fd, &termios_p);
termios_p.c_cflag = B9600;
[Code]....
I am writing a program to read and write to devices over my serial port. My program will need to connect to up to four other machines at once. I can connect to machines successfully, it works well. However, after I connect and disconnect once, attempting to connect again will cause the FIRST serial connection will fail and all the ones after it will pass.
e.g.
Code:
fd[0]=connect("/dev/ttyS0");
fd[1]=connect("/dev/ttyS1");
fd[2]=connect("/dev/ttyS2");
fd[3]=connect("/dev/ttyS3");
code....
That works as long as it is executed only once in the program. The second time it is executed, fd[0] will die and fd[1-3] will work normally.I can't figure out why this happens, but I found a workaround by connecting to "/dev/null" before any real serial ports.What should I do?
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Code:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
[code].....
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[code]...
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[code]...
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