Elektron Musical Instruments

i just bought a sid station from a friend of mine and it froze up on 
me.  i have no idea what os it is running.  one day it was working, 
the next it was not.  

it powers up and the screen lights up but there are no letters or 
numbers in the display.  the contrast knob still works.  no midi 
communication though.

please help!

thanks.