IC question

[iwillbeacircuitbender]

This is an IC from an old stereo that my cousin doesn't use anymore
It's a yamaha branded chip, with a model number of MB90F830
What the heck is the function of this chip?
ROM?
CPU?
Or display driver?

[phlogister]

Search for a datasheet. Couldn't find the exact match, but it's most likely a 16 bit microcontroller http://www.alldatasheet.com/view_datasheet.jsp?aPage=1&sField=2&sSearchword=MB90F8&seekcls=&sPage=2&chkAll=ON&sDATA=56%2CFUJITSU%28107%29%3B842%2CETC1%286%29%3B&hapsu=113&tnoa=113 , may be mask-programmed, maybe not.

[iwillbeacircuitbender]

You are certainly correct. Looks like a rebranded Fujitsu IC