How to access basic cube data as part of update rule routine?

Dear colleagues:

I am developing a routine as part of the update rule to define a characteristic value to feed an infocube. However, I need to peek up a data that is available on another infoprovider, in this case a basic cube.

So far, I have done that by peeking up data form ODS as part of the update routine, but this is the first time I need to peek up a data from a basic cube.

<b>Does that works the same way as ODS?</b>

Best regards

Waldemar