ADuC812 Dac

Hi, Im new to using microcontrollers and I am having some trouble
using the ADuC812. I want to use the DAC0 to output a certain voltage
which I specify . I think that it has something to do with setting the
values of DAC0L and DAC0H but I am not sure how it works.
I've searched for the answer online but without any luck.

Any help would be greatly appreciated.

Thanks in advance.