Pie Chart based on Range in Excel

Is there any tutorial on how to create a PieChart in excel based on Cells Range?

In MSDN I've found this article http://msdn.microsoft.com/en-us/library/office/cc820055.aspx but it dealt with bar chart and it accepts data from a dictionary, I need to be able to create a pie chart using a range of cells as data source.

Thanks for any help.

Gian Maria.

Ricci Gian Maria. (http://www.codewrecks.com)