audio programming de2 board using c or assembly

I am kind of stuck in ways to generate different notes that can be sent to the audio codec to be outputted. According to the datasheet, the audio codec works as 16 bit sampling at 48 Khz. I was wondering if someone could show me sample code in outputting a simple note of lets say 440 Hz.

Few notes... I am programming on the DE2 board so the library usage is very limited (functions like the Beep function will not work).

I dont want to do this in verilog or vhdl... only in C or assembly. Thank you to anyone that can help.

If you know of any good tutorial places for these specs (in C or assembly using DE2) would also be appreciated.