Disable blanking the text terminals.
Jessie
Open:
$ sudo nano /boot/cmdline.txt
Addd:
consoleblank=0
Wheezy
Open:
$ sudo nano /etc/kbd/config
Change to:
BLANK_TIME=0 BLANK_DPMS=off POWERDOWN_TIME=0
Or add in:
$ sudo nano /etc/rc.local setterm -blank 0
Blanks the console after 10 seconds.
Jessie
Open:
$ sudo nano /boot/cmdline.txt
Addd:
consoleblank=10