Scramble arcade- what was the second Z80 cpu used for?

[gunrock]

As the thread title, what would the second Z80 cpu have been used for? Sound code?

Seems unlikely, it's hardly a musical/fx tour-de-force.

Edit: Primarily asking the Jamma cab boys, etc.

[Brad]

It was indeed for the sound. Not actually emitting the sound I guess, maybe instructing what sounds should be played.