Woz wrote about it in his book which came out about 5 years before Jobs death. Here’s an interview from 2008 where he discusses it:

Knowledge at Wharton: In the book you also recount how, when you developed Breakout for the Atari, Steve Jobs sold it and told you that he received $700 for the two of you to split while, in fact, he had been paid a few thousand dollars. Although, in hindsight, the money is rather irrelevant, how do you feel about the ethics of this?

Wozniak: Yes, the money’s irrelevant — and it was then. I would have done it for free. I was happy to be able to design a video game that people would actually play.

I think Steve needed money and just didn’t tell me the truth. If he’d told me the truth, he’d have gotten it.

He should have known me well enough to just come out and say he needed the money. It would sound odd, me doing the entire design and him getting all the money. I would have done it. He was a friend. You help your friends.