Chevrolet: 99 S-10 Battery Warning Light, altanator, warning light

Question
This morning, about 100 yards from my driveway, my battery light came on. The gage indicated 12 volts charging. All accessories work. I turned of the vehicle, turned on the key. The gage indicates 12 volts without the engine running. It seems the battery is okay. Drove 15 miles to work, parked for 8+ hours. Engine started fine. Drove 15 miles home. Other than the battery light is on, no other problems are evident.

Answer
Larry ;
 HI - well you might have trouble with your altanator , as 12 volts charging is not enough - your battery will soon go dead , the altanator might have a bad dioede and it is not putting out enough juice as it should be close to 14+ so check the alt. out.   ok >>>
Roger JM W