how to repeatedly call a function while macro is running

[guest]

How do i guest a macro- to call out a userdefined function only at specific times. What i mean is If i wanted to have a macro do a specific task like check email or something, and have it open a notepad every 3 minutes , how do i get it to run the macro, but only have the function timed at 3 minutes to open a notepad, but keep the other task of the macros running constantly?