You would need 16 sensors, one for each compartment.
Being a bit more serious, I personally need no more information than I'm already getting, just serve it up like my GPS for driving.
Some sweet female voice whispering in my ear: "You're ten minutes into deco, Hon. You best start up now or you'll be sucking a pony to get home..."
I am all for the soothing sweet sounds of a woman telling me it is time to ascend to my safety stop depth.