title: FTDI Device not detected
body: <p>After connecting an FTDI device to the USB port, <code>FT_OpenEx()</code> returns an error code 2 which is <code>FT_DEVICE_NOT_FOUND</code>. However on running "lsusb" in the terminal, the FTDI device does show up. 
  What is causing <code>FT_Open_Ex()</code> to return <code>FT_DEVICE_NOT_FOUND</code> if the device is listed by lsusb? What are the possible issues and solutions?</p>
  
  <p>Output of lsusb:</p>
  
  <pre><code>Bus 001 Device 003: ID 0bda:5776 Realtek Semiconductor Corp. 
  Bus 001 Device 002: ID 8087:8000 Intel Corp. 
  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
  Bus 002 Device 003: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC
  Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  </code></pre>
  
  <p>Output of dmesg | grep FTDI : </p>
  
  <pre><code>[28153.244220] usbserial: USB Serial support registered for FTDI USB Serial Device
  [28153.244260] ftdi_sio 2-1:1.0: FTDI USB Serial Device converter detected
  [28153.244509] usb 2-1: FTDI USB Serial Device converter now attached to ttyUSB0
  </code></pre>
  
  <p>Output of dmesg | grep -i FTDI:</p>
  
  <pre><code>[28153.244206] usbcore: registered new interface driver ftdi_sio
  [28153.244220] usbserial: USB Serial support registered for FTDI USB Serial Device
  [28153.244260] ftdi_sio 2-1:1.0: FTDI USB Serial Device converter detected
  [28153.244509] usb 2-1: FTDI USB Serial Device converter now attached to ttyUSB0
  </code></pre>