Target Serial Access

It is useful to be able to get a terminal on your target device. This page lists some options for this. Instructions assume Ubuntu Lucid and a 115200 serial link.  Also you should be using a serial null modem cable.

USB Serial Dongle

This is a common way of getting a serial port on a computer. See TRENDnet USB to Serial converter for example.

ser2net

This is a convenient tool which allows you to 'telnet' into your board over a serial link. These instructions assume you are using a single USB serial dongle (/dev/ttyUSB0) but you can also use a real serial port (/dev/ttyS0) if you like. If you have an FTDI serial device providing serial access then it will use /dev/ttyACM0.

sudo apt-get install ser2net

Edit /etc/ser2net.conf and add this line:
4000:telnet:600:/dev/ttyUSB0:115200 8DATABITS NONE 1STOPBIT banner

Then restart so that ser2net sees your changes:
sudo /etc/init.d/ser2net restart

You can now connect to the board with:
telnet localhost 4000
To disconnect, press Ctrl-\ then Ctrl-D.

screen

Screen is a useful tool for maintaining connections which you can switch between easily. It is often used to run a long-running job such that you can logout, then later login, reconnect and check progress. You can also use screen to get a serial link:

screen -t 'ttyUSB0 115200 8n1' /dev/ttyUSB0 115200,-ixoff,-ixon

Reset the machine and U-Boot should start printing to your terminal.

For help, use Ctrl-A Ctrl-?. To disconnect, press Ctrl-A Ctrl-D and to quit the session Ctrl-A Ctrl-\

minicom

Minicom is a terminal program, intended for use with a modem, that
works well as an intermediary to any remote system connect through a
serial port.

One big advantage of minicom is that it allows one to easily capture
text into a file.

Minicom Installation

To install minicom, execute the following
 
  sudo apt-get install minicom

Minicom Configuration

  sudo minicom -s

The configuration is done through a simple menu system.  Use the options below for a basic working configuration.

  Select 'Serial Port Setup' using the arrow keys; press <Enter>
  Select 'A': enter the name of your serial port.  (ex: /dev/ttyUSB0)
  Select 'E': select 'E' (115200), then 'Q' (8N1)
  Set 'Hardware Flow Control' to 'No.
  Set 'Software Flow Control' to 'No'.
  Press <Enter>; this brings you back to the main menu (titled '[configuration]')
  Select 'Save setup as dfl'; press <Enter>.
  Select 'Exit from Minicom'; press <Enter>.

Execution

  Minicom needs access to the configured serial port.  This means you
  either need to change the permissions on that port to allow your
  normal user to access the port in read/write mode, or run using
  'sudo'.

sudo minicom

Minicom commands

  All commands are prefixed with <Ctrl-A>, which will be abbreviated
  C-a.

 Key Result
C-a Z
Opens interactive menu
C-a C
Clear Screen
C-a LPrompt for capture log file name.
C-a L(after opening log file) Pause or close log file
C-a Q
 Quit (w/o modem reset)
C-a X
 Quit immediately
C-a EToggle  echo of locally typed characters
C-a W
Toggle Line Wrap
C-a T
Select terminal settings

ssh

Once you have network access, and assuming you are using a test build, you can use ssh to connect to your target.

ssh chronos@192.168.2.3
(password test0000)

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