The Raspberry Pi has a built in UART. This can be use as a serial port console. To connect to laptop a 3.3v FTDI breakout board is used.
If a monitor and ethernet connection is not available and you need to see the boot up message a serial console is a possible solution. Using a 3.3v FTDI breakout board, wire up the connection as shown:
To use it as a console, minicom software would need to be install first.
sudo apt-get install minicom
Then start the software:
minicom -b 115200 -o -D /dev/ttyUSB0
On your laptop start the terminal software and set it to baud rate to 115200. You should then get the console output like this:
You can now logon as normal.
Just out of curiosity (and my complete noobness), what can this be used for? What can be attached to the breakout board?
If somebody could give me a little bit of information as to what this can be used with I would like to try this project.
My impression is this would be really handy for twiddling with the RasPi on the go. It removes the need for a display, keyboard, mouse, network. Just talk to it directly over usb/serial console from a host computer (your laptop for example).
installetion problem in minicom mirror directory how to solve this problem