Ubuntu
USB

Setup Device to USB Serial Port (ttyUSB) example with Kondo Kagaku Servo Motor

More than 1 year has passed since last update.

When you sometimes plug in a device to your PC but it cannot detect to ttyUSB Port, you should do following action:

First: Check the device ID

   $ lsusb
   Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
   Bus 003 Device 003: ID 165c:0009 Kondo Kagaku 
   Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
   Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
   Bus 001 Device 004: ID 0bda:0153 Realtek Semiconductor Corp. Mass Storage 
   Device
   Bus 001 Device 003: ID 8087:0a2a Intel Corp. 
   Bus 001 Device 006: ID 1a81:1004 Holtek Semiconductor, Inc. 
   Bus 001 Device 005: ID 2047:0200 Texas Instruments MSP430 USB HID Bootstrap 
   Loader
   Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Second: Lets say we want to direct "Kondo Kagaku" Device to USB device, there is 165C:0009 represent vender_id:product_id
Do the following action to activate it

   $ sudo modprobe ftdi_sio
   $ sudo su
   root@$ echo "165C 0009" > /sys/bus/usb-serial/drivers/ftdi_sio/new_id
   root@$ chmod 666 /dev/ttyUSB0
   root@$ exit

and now you should able to access the port /dev/ttyUSB0!

If you want to fix the port, please refer to this site: https://qiita.com/osada9000/items/3e6ff429ba782624def1