Hi June,
The Basic Function Generator.vi outputs a waveform/array while the AO Write One Update.vi reads a single value so its not the right AO vi to be used for signal generation.
You can use the intermediate AO Write.vi in conjuction with the function generator vi.
Much easier, have a look at the a shipped AO example in labview for a start.
There is shipped example called 'Function Generator.vi' that is a advanced example of continuous waveform generation. It generates the selected waveform continuously until the stop button is pressed. It changes the waveform on the fly, responding to changing signal type, amplitude, offset, point rate, and phase settings on the front panel.
Hope this helps,
Pravin
