newcomer! help me

i have learned 89c51 this semester, and now i have a weekly project but have no exper. before, so would you help me ?
req:- use adc0809 ,89c51, dac0808
- the input signal : analog/digital --> (adc)--> 89c51 + ram
when ram is full --> led
- then : data --> (dac)--> output(led 7 seg./...)

but : 8 analog inputs, 2 digital inputs+ 2 analog outputs, 2 digital outputs
i can't understand how it works, do you have any experiment ?

my email : sixday06@yahoo.com

thanks

i don't understand your problem,i have some but i don't know what do u need exactly.