RPi Serial Connection

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Back to RPi Advanced Setup.


The Serial Port is a simple and uncomplicated method to connect to the Raspberry Pi. The communication depends on byte wise data transmission, is easy to setup and is generally available even before boot time.

First interaction with the board

Connect the serial cable to the COM port in the Raspberry Pi, and connect the other end to the COM port or USB Serial Adapter in the computer.

How please? I'm led to believe it's wired at the board end, so needs an accessible 9?? pin male|female 232 connector, then some sort of serial to usb dongle. Any more information on this please?

Next is this the preferred way to get low level access to the board, or using the usb for kbd and hdmi for screen?

Serial Parameters

The following parameters are needed to connect to the Raspberry. All parameters except Port_Name and Speed are default values and may not need to be set.

  • Port_Name: Linux automatically assigns different names for different types of serial connectors. Choose your option:
    • Standard Serial Port: ttyS0 ... ttySn
    • USB Serial Port Adapter: ttyUSB0 ... ttyUSBn
  • Speed: 115200
  • Bits: 8
  • Parity: None
  • Stop Bits: 1
  • Flow Control: None

The Serial Port is generally usable by the users in the group dialout. To add oneself to the group dialout the the following command needs to be executed with root privileges:

 $useradd -G {dialout} your_name 
  • Super Easy Way Using GNU Screen

Enter the command below into a terminal window

 screen Port_Name 115200
  • Super Easy Way Using Minicom

Run minicom with the following parameters:

minicom -b 115200 -o -D Port_Name
  • Tedious Old-Fashioned Way Using Minicom

Another method to setup minicom is described in the Tincantools Minicom Tutorial


  • GUI method with GtkTerm

Start GtkTerm, select Configuration->Port and enter the values above in the labeled fields.


  • Windows Users

Windows Users above Windows XP must download putty or a comparable terminal program. Users of XP and below can choose between using putty and Hyperterminal.

First Dialog

If you get the prompt below, you are connected to the Raspberry Pi shell!

 prompt> #

First command you might want try is "help":

 prompt> # help

If you get some output, you are correctly connected to the Raspberry Pi! Congratulations!