I did this once with Debian to control an Arduino board with a PHP script and initially ran into the same problem.In Debian, you need to add the Apache user to the dialout group in order to allow it to make serial connection requests. I would assume the same is true for Fedora.In Debian the command is: useradd -G dialout www-dataHowever I believe Fedora names the Apache user as apache instead. I don't have a Fedora machine to test on, but I would assume the command you need to run is: useradd -G dialout apacheYou will then need to restart your xampp server.See the following for reference:Neal.

• Linux Serial Port Programming Example
• Php Serial Port Read Example

Opening the serial port resets that Arduino, unless you have modified the Arduino to not reset when the serial port is opened. Have you?As it is now, you open some serial port. Without opening a bunch of files, I can't see which one. Nor do I have any clue if that is the right one. As soon as the port is opened, while the Arduino is resetting, you send two characters and close the serial port, resetting the Arduino again.No matter which language you use to open the serial port, the Arduino will reset. No matter what language you use to close the serial port, the Arduino will reset. Unless you modify it not to.The key, then, is to open the port, wait while the Arduino resets, and then send it data.

When you are done with the Arduino, close the serial port. :-)))))If I understand you right, you just found a php script for serial communication and opened it with your webbrowser. If so, here are some hints that may help you:- a php script can basically well be executed without browser. Remove the starting ', than it may already work. (by executing it with a php interpreter)- if you want to run an embedded php script, you cannot just open it in a browser from your local drive.

It must be requested via a webserver, and the webserver, if configured properly, will do the php execution for you. But this is surely not what you are looking for, as it is unnecessary complicated.

Linux Serial Port Programming Example

Hey thanks a lot guys.sorry to bother you again.i was opening the file directly from browser from the location htdocs.i changed the file location to htdocs/xampp and it has started executing but there are some warnings as below:Warning: Specified serial port is not valid in /opt/lampp/htdocs/xampp/phpserial.class.php on line 147Warning: Unable to set the baud rate: the device is either not set or opened in /opt/lampp/htdocs/xampp/phpserial.class.php on line 241Warning: Unable to set parity: the device is either not set or opened in /opt/lampp/htdocs/xampp/phpserial.class.php on line 295. I have used the command: chmod 0777 /dev/ttyUSB0 to give permissions. I have also tried to add the apache user 'prudhvi' to the dialout group by using command: $ usermod -a -G dialout prudhvi.But it doesnt work. When I send a command directly from the terminal using the command: echo 1 /dev/ttyUSB0 it works and '1' is transmitted to the serial port. But using php I get the above warnings.I have used the '$whoami' to check name of user and added that user 'prudhvi' to the dialout group. It still doesnt work.

Php Serial Port Read Example

Please help me guys.