PuTTy Conenction type:
Serial
Step 1: Check your serial port for debug board
Step 2: Just type “115200” baud rate.
Note: Some standard baud rate 9600,19200,38400,57600 and 115200 if necessary.
Step 3: Select “Serial” for connections type.
Step 4: Just type “Com port COM1” whatever name you like.
Step 5: Click “Save” button to save your configuration.
Step 6: Click “Open button.
Note: Please check your COM1 and make sure it works well.
http://nanopc.org/dev/466.html
You will see following interface.
Note: No need username and password.