As noted by DiveNAv, the OC1 shows your current deco stop information (depth and time) on the main screen, and your total ascent time on the Alt 1 screen. You cannot directly see what your next deco stop is until you have cleared the current stop. So if
your TAT exceeds your ATR, breathe less unless you are carrying a deco cylinder. The OC1 works pretty well for gas switches when using nitrox to accelerate deco, but the OC1 calculations are based solely on the data from the tank sensor that you have selected.
The Buhlmann algorithm favors long deco stops at a relatively shallow depth. So if you don't have the deep stop option turned on, you will most likely be facing an extended stop at 10 feet, and significantly shorter stops at slightly deeper depths when you have a more significant deco obligation.
Personally, I prepare a dive plan for all deco dives and use my computers as a backup. That was I know what deco stops to expect and how much gas I have in reserve.