I was using a gateway to send sms ( nowsms ) but the evaluation period ended and I went to buy the license, $ 995 to send 12 sms per minute, I did not find it viable.
Searching I found a Php-Serial class ( link ) but I can not send anything to the modem, it always gives error to the indicate baud rate .
Has anyone done anything similar that can help me?
The message baud rate seems only part of the error, you should be more specific about which error occurs.
An example that you can use to detect the crash is:
Run the command by CMD:
mode COM17 xon=on BAUD=9600
If the port were COM20 then the command would be:
mode COM20 xon=on BAUD=9600
With this you can detect the error (if the modem is supported for example)
%SystemRoot%\system32\control.exe or open the control panel Modem (COM 17)
In case if the port is 17 the script should look something like:
<?php
include 'PhpSerial.php';
$serial = new PhpSerial;
$serial->deviceSet('COM17');
...