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{{Article summary text|This article covers the configuration of udev for Arduino Communication.}}
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==Summary==
If you use more than one Arduino with USB or have other USB-to-Serial devices, then you may find it convenient to make the device have the same name every time you reboot or connect the Arduino. The technique here is shown for an FTDI device, but the same process can be used for just about any USB-to-Serial device that the system recognizes.

==Assumptions==
* You are familiar with the Linux command line
* You understand basic text file configuration methods
* You are familiar with serial communications in Linux

==Installation==

{{Note|All scripts will assume that there is a '{{ic|/dev/arduino_1}}'.}}

The drivers for the FTDI chip is included in the kernel, so it should be detected as soon as it's plugged in, and assigned to device {{ic|/dev/ttyUSB[0-9]}}.
To check where it got assigned, run:

  dmesg | grep FTDI

The output will contain a line that looks something like this:

  usb 1-4.4: FTDI USB Serial Device converter now attached to ttyUSB0

===udev===

It can be annoying to have to look up what {{ic|/dev/ttyUSB[0-9]}} the device gets assigned, so it's a good idea to add a simple udev rule that creates the renames the device when it is plugged in.

First of all, you will need to find out the serial number of FTDI chip on the bus pirate. This can be achieved by running the following, assuming your device is plugged in and was assigned to {{ic|/dev/ttyUSB0}}:

  udevadm info --attribute-walk -n /dev/ttyUSB0

Now add/create the following file:

{{hc|/etc/udev/rules.d/98-arduino.rules|2=
<nowiki>
SUBSYSTEMS=="usb", ATTRS{serial}=="XXXXXXXX", ATTRS{product}=="FT232R USB UART", ATTRS{idProduct}=="6001", ATTRS{idVendor}=="0403", NAME="arduino_1"
</nowiki>}}

Change 'ATTRS{serial}=="XXXXXXXX"' to the serial on your device and force udev to load the new rule:

  udevadm control --reload-rules

At this point, whenever you plug in the device, the device should be renamed to {{ic|/dev/arduino_1}}. You can rename more by adding more lines to the rules file and extract the serial number for each device and of course name it what ever you like. The same process can be used for other USB-to-Serial devices as well. 

==Communication==

To communicate with the device, you can use any of the following, to name a few:

* {{ic|minicom}}
  minicom -b 115200 -8 -D /dev/arduino_1
* {{ic|screen}}
  screen /dev/arduino_1 115200 8N1
* {{ic|picocom}}
  picocom -b 115200 -p n -d 8 /dev/arduino_1
* {{ic|putty}} - gui utility
 putty -serial /dev/arduino_1 -sercfg 115200,8,n,1,X
* {{ic|plink}} - cli utility
 plink -serial /dev/arduino_1 -sercfg 115200,8,n,1,X