Regarding DAC

Using Arduino Audio
1

I need to access the DAC Pin on arduino due,How to do ,what type of function to be used pls clarify as i am a Learner

2

First you need to set the resolution with
analogWriteResolution(12)

http://arduino.cc/en/Reference/AnalogWriteResolution

Then you write
analogWrite(DAC0, val)
Where val is the 12 bit value you want to write
and
DAC0 or DAC1 is the pin you want to use.
Note that these are delicate pins and do not load them with more than 1K1 for sourcing or 510R for sinking.
That is it will only source 3mA and sink 6mA

3

Will u pls Provide me an example program for controlling Buzzer sound using DAC

4

salaideva:
Will u pls Provide me an example program for controlling Buzzer sound using DAC

What sort of buzzer and what sort of sound?

You do not normally feed a buzzer with the output from a DAC so this seems an odd request. As I said you will need some hardware as well you can't just connect a buzzer to a Due.