You can program each compartment to open in 2-hour intervals. Set each dial for when you want each compartment to open and allow your pet to eat a meal.
For example, if you feed your pet once a day and he just ate a meal, set the first dial to 24 and the second to 48. The first compartment will open 24 hours from now. If you feed your pet twice a day and he just ate a meal, set the dials to 12 and 24. The first compartment will open in 12 hours.