====== How to change the serial port =======

If you did not see ''/dev/ttyUSB0'' in the device list, and you could not see anything matching your device, you will need to make sure the serial device is connected and supported by Linux. Then try the following:


===== Finding out the name of the serial device =====
If you do not know what your serial device is called, you can do the following.

  * Make sure the USB serial adapted is connected. Then run ''**ls** /dev/tty*''. 
  * Disconnect the serial device and run ''**ls** /dev/tty*'' again. Did you notice something missing compared to the previous printout? 
  * Now connect the serial device, wait 5-10 seconds and run ''**ls** /dev/tty*'' again. Do you see a new device in the list? 
  * If you do not see a new serial device, the device may not be compatible with Linux. Run ''**dmesg**'' to see if it is detected. In my case it is detected, and is named **ttyUSB0**:
{{ :guides:pics:vmodem_raspberry_serial_dmesg.png |}}
//Ignore the under-voltage error on my screenshot. You shouldn't be getting that error.//
===== Update vmodem.sh script =====
  * To change the serial port used in the **vmodem.sh** script, do the following:
  * Run ''sudo nano /boot/vmodem/vmodem.sh''
  * Find the line ''serport=ttyUSB0'' and update it to reflect the correct serial device. 
    * For example, if your USB device is called "/dev/ttyAMA0", then make sure the line says ''serport=ttyAMA0''. 
  * Save file by pressing **CTRL + o**, then ENTER to save under the same name. 
  * Exit editor with **CTRL + x**.

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