Even though it's a completely different style, I'd say that trashcan it's connected to (through the wall) is its computer. Could ya turn it on ?

Edit: Then use the computer .

...how do I operate this?

Is that an oscilloscope ? Try speaking into it to see if it's hooked up to a microphone and observe the cool waves.

Then hit one of the buttons to turn it on.

Try mashing the buttosn randomly until crap happens.

seconded

Thanks for fixing my typo.

Also Thirded

push some buttons, whats the worse that could happen?

The world blows up?

...Yeah...how...exciting. :/

Do them in backwards order, last to first, as that would be how you'd play YMCA on it.

Give it a kick.

throw all your naughty pictures at it. I know you have them!

or

paste green flesh onto screen

or

eat green flesh

hmm... try pressing leftmost one, rightmost one, leftmost, leftmost, rightmost, leftmost.

push them all at the same time

Consult your memory, maybe he saw someone use a similar machine before ?