Hello everybody.

[Belisarius]

I am making a VI for data acquisition from a DAC card.
How can I make my VI not to ask for a directory nor a filename when it has to make a new data file and instead make it name the file after 2 strings that i can change everytime.
example: cyl1-rpm1000.dat

[RobertoBozzolo]

In the File I/O palette you will find everything you need.
Both Write to Spreadsheet File.vi and Write Characters to File.vi accept a file path as an input: if you wire a correct file path to it the dialog box will not show and the vi will use directly the file you said.
Write File.vi accepts a refnum as an input: the refnum is the output of Open File.vi (File I/O \ Advanced File Functions palette); again, you have to wire a path to an input of Open File and that file will be used.
To build the path for your file you can use a Concatenate Strings to create the final name and the Build Path.vi to create the complete path to the file you want to use.
Hope this helps
Roberto