number of step to be hour

[ch2324]

Hi everybody,
i have data with frequency interday (30 minute step) from 01/01/2000 09:00 30/11/2005 10:00, how can calculate the number of step between two hour by function?,
for example between 08:00 08:30 and 08:30 09:00, the step here is two because in hour there is 60 minute divided by 30 minute, number of step equal 2.
if the frequency will be (20 minute step) 60 minute divided by 20, numbre of step equal 3.
if the frequency will be (10 second step) 3600 second divided by 10, numbre of step equal 360.