Serial Port communication issue

[unisabilly]

Good day all :

I have an issue here, i try to use php to send the SMS via my 3G USB modem, as I try to send it with hyperterminal, it works perfectly with COM port number 27.

as I try to fopen COM port 27 it return with the following error message : Warning: fopen(COM27:) [function.fopen]: failed to open stream: Invalid argument in C:\AppServ\www\home\test\sms\com_connect.php on line 4

 

but if i fopen the COM port 1 to 4, it actually connected to the COM port, which means I can only connect to COM port 1 to 4, from COM5 onward, i wont be able to connect. any idea why ?

 

exec("mode COM27 BAUD=9600 PARITY=N data=8 stop=1 xon=off");  
$fp = fopen ("COM27:", "w+"); 
if (!$fp) 
{    
echo "Not open"; 
} 
else 
{
echo "opened";
fclose($fp);	
}

 

P.S. I use the port monitor software to monitor the ports, when I connect to COM port 1-4 it actually receive the request, but it receive nothing when I try COM5 onward.

and I'm running apache on windows. please help. and thank you in advance

[Christian F.]

You could try the php_serial class and see if that helps, if not the PHP-DIO library might help.

If neither does, then it might be a problem caused by the virtual status of that COM port. Which will require some further investigation, and probably a call to the USB device directly (avoiding the virtual COM port).

[unisabilly]

Thank you Christian for the reply, I have no luck with php_serial_class, and PHP-DIO gave me the same result as fopen, ie only works with port 1 t0 4, I found some articles regarding to the same issues, seems like it works fine with ubuntu but not with windows. I have no idea why    is there any way to work around the issue, except for changing the OS