How to do Integration with Flat Files?

Hi all,   I need data from flat files like(CSV, txt, etc.)  and I followed some integration processes using the flat interface module but was unable to receive the output.  any guidance will be helpful to me?
1 answers

Are you using the flat file importer?

In general there are multiple modules that you can use. 
For example:

For both modules try and use the documentation that is there to set it up. 
If you have a specific question let us know;)